Develop Reference

2 DropDownLists on each row of Gridview

I have a gridview that is being dynamically created based on the database. Some rows of the gridview have 2 DropDownLists, while others do not depending on the item in the row. The second DropDownList of the row is dynamically created based on the selection of the first DrowpDownMenu. Everything works as it should except, if you make the selections on the first row, then change the selection of the first DropDownList of the seccond row or click the update button, it will reset the second DropDownList of the first row. This is obviously due to PostBack. But I'd like to maintain the selection until all DropDownLists have been selected and I save the changes to the DB. Any help would be very appreciated.
My Gridview:
<asp:GridView ID="CartList" runat="server" AutoGenerateColumns="False" ShowFooter="True"
GridLines="Vertical" CellPadding="4" CssClass="table table-striped table-bordered"
OnRowDataBound="CartList_RowDataBound">
<Columns>
<asp:BoundField DataField="ProductID" HeaderText="ID" SortExpression="ProductID" />
<asp:BoundField DataField="Product.ProductName" HeaderText="Name" />
<asp:BoundField DataField="Product.UnitPrice" HeaderText="Price (each)" DataFormatString="{0:c}" />
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:TextBox ID="PurchaseQuantity" Width="40" runat="server" Text='<%# Eval("Quantity") %>'></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Size">
<ItemTemplate>
<asp:DropDownList ID="Sizeddl" runat="server" Font-Size="Medium"
AutoPostBack="true" ForeColor="Black" OnSelectedIndexChanged="Sizeddl_SelectedIndexChanged">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Color">
<ItemTemplate>
<asp:DropDownList ID="ColorNameddl" runat="server"
Font-Size="Medium" ForeColor="Black">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Item Total">
<ItemTemplate>
<%#: String.Format("{0:c}", ((Convert.ToDouble( Eval("Quantity") )) * Convert.ToDouble(Eval("Product.UnitPrice"))))%>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Remove Item">
<ItemTemplate>
<asp:CheckBox ID="Remove" runat="server"></asp:CheckBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<div>
<p></p>
<strong>
<asp:Label ID="LabelSubtotal" runat="server" Text="SubTotal: "></asp:Label>
<asp:Label ID="lblSubtotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTax" runat="server" Text="Tax Total: "></asp:Label>
<asp:Label ID="lblTax" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTotalText" runat="server" Text="Order Total: "></asp:Label>
<asp:Label ID="lblTotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
</div>
<br />
<table>
GridView Load:
DataTable rstSize = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
decimal cartTotal = 0;
cartTotal = usersShoppingCart.GetTotal();
if (cartTotal > 0)
{
// Display Total.
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
}
else
{
lblSubtotal.Text = "";
lblTax.Text = "";
lblTotal.Text = "";
ShoppingCartTitle.InnerText = "Shopping Cart is Empty";
UpdateBtn.Visible = false;
CheckoutImageBtn.Visible = false;
}
if (!IsPostBack)
{
LoadGrid();
}
}
}
void LoadGrid()
{
// Load Cart Items.
using (ShoppingCartActions actions = new ShoppingCartActions())
{
var _db = new ProductContext();
string cartId = actions.GetCartId();
var cart = _db.ShoppingCartItems.Where(
c => c.CartId == cartId).ToList();
// Create DataTable for Colors
rstSize.Columns.Add("SizeName", typeof(string));
var row = rstSize.NewRow();
row["SizeName"] = "S";
row["SizeName"] = "M";
row["SizeName"] = "L";
row["SizeName"] = "XL";
row["SizeName"] = "2XL";
CartList.DataSource = cart;
CartList.DataBind();
// Hide DropDown Lists for rows that they are not needed for.
for (int i = 0; i < CartList.Rows.Count; i++)
{
DropDownList sizeDDL = CartList.Rows[i].FindControl("Sizeddl") as DropDownList;
DropDownList colorDDL = CartList.Rows[i].FindControl("ColorNameddl") as DropDownList;
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
var _prodID = Convert.ToInt32(rowValues["ProductID"]);
var _prod = (from c in _db.Products
where c.ProductID == _prodID
select c.CategoryID).FirstOrDefault();
if (_prod != 1)
{
sizeDDL.Visible = false;
colorDDL.Visible = false;
}
}
}
}
My RowDataBound:
protected void CartList_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem;
// Populate and select Color from DB.
DropDownList sizeDDL = (DropDownList)e.Row.FindControl("Sizeddl");
sizeDDL.DataSource = rstSize;
sizeDDL.DataBind();
sizeDDL.Items.Insert(0, new ListItem("Select Size", "0"));
sizeDDL.SelectedValue = gData["SizeName"].ToString();
// Load Color DDL
var _size = sizeDDL.SelectedItem.Text;
int _prod = Convert.ToInt32(e.Row.Cells[0].Text);
var _db = new ProductContext();
var qryColor = (from p in _db.ProductAttributes
join c in _db.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prod
select new { p.ColorID, c.ColorName }).Distinct().ToList();
DropDownList colorDDL = (DropDownList)e.Row.FindControl("ColorNameddl");
// Create DataTable for Colors
DataTable rstColor = new DataTable();
rstColor.Columns.Add("ColorID", typeof(int));
rstColor.Columns.Add("ColorName", typeof(string));
foreach(var item in qryColor)
{
var row = rstColor.NewRow();
row["ColorID"] = item.ColorID;
row["ColorName"] = item.ColorName;
rstColor.Rows.Add(row);
}
// Bind Color Drop Down List to DataTable.
colorDDL.DataSource = rstColor;
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.SelectedValue = gData["ColorName"].ToString();
}
}
My SelectedIndexChanged
protected void Sizeddl_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList sizeDDL = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)sizeDDL.NamingContainer;
string strSize = sizeDDL.SelectedItem.Text;
DropDownList colorDDL = (DropDownList)gRow.FindControl("ColorNameddl");
if (strSize != "Choose one")
{
using (ProductContext context = new ProductContext())
{
int _prodID = Convert.ToInt32(gRow.Cells[0].Text);
var _size = sizeDDL.SelectedItem.Text;
var qryColor = (from p in context.ProductAttributes
join c in context.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prodID
select new { p.ColorID, c.ColorName }).Distinct().ToList();
if (qryColor.Count > 0)
{
colorDDL.DataSource = qryColor;
colorDDL.DataTextField = "ColorName";
colorDDL.DataValueField = "ColorID";
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.Enabled = true;
}
else
{
colorDDL.Items.Clear();
colorDDL.Items.Insert(0, new ListItem("No Colors Available", "0"));
colorDDL.Enabled = false;
}
}
}
}

if you make the selections on the first row
By "selections" are we to assume make changes - or select/change a value in the combo boxes, right?
I'd like to maintain the selection until all DropDownLists have been selected and I save the changes to the DB. Any help would be very appreciated.
A grid view will and should handle post backs on the page. After all, even outside of the GV, any old button or control can and will cause post-backs.
There is no reason that changes to ANY grid row by users, and that includes drop down lists (DDL) should matter. And operations on one row should not effect operations on other rows. The so called "view" state of the GV is automatic, and for the most part you should not have to worry.
So, it not at all clear why you posted the "add row", since all of this question centers on editing or making changes to the current row. (for us, say next week or when ever, we can look at or deal with the row created, but for now lets concentrate on the changes to a given row, and why for some reason you see effects in other rows - you should not be seeing this.
Tops on the list?
While controls - including a GV can and should handle post-backs without issue?
That is NOT the case if a post-back causes a re-bind of the grid. If that is to occur, then you going have issues.
So, tops on the list?
You left out how/when/where you are loading up the GV.
(the MOST important part!!!!).
Next up?
You do NOT want nor need to show the row PK id in the GV. These numbers not only mean nothing to the end user but it also a security risk - PK row numbers don't need to be displayed, and in fact do not even need to be included in the row markup. We again can leave that issue for another day, but you can (and should consider) using DataKeys for the row PK id operations. We assume no duplicate PK row id in the database, right? In other words, make sure you have a database row PK "id" in your data.
So, you can in the future, remove that ProductID. GV has a special feature for dealing with the PK row id - and we should be using that. (Datakeys)
Ok, now that we cleared up the above?
In the page load event, we need to load the GV, but ONLY on first page load - after that, we can't re-load the GV (bind again), else you WILL lose your changes, and edits to the GV.
Also, you might want to consider a save button at the bottom - to save all gv changes - in place of doing this row by row. (but, one thing at a time here).
So first up, the code to load the GV, should be in page load.
Next up, that code has to ONLY run the first time.
eg:
if (!IsPostBack)
{
code here to load GV
}
Next up? when the GV is loaded with that data, you need to setup the combo box and the cascade. And further more, this setup of each row should occur in the row data bound event.
So, your posted code does look ok, but we missing how/when you load the GV.
And we don't see your save button either. But at this point, I would share your code that loads up the GV - this all important information is missing here.
So edit your question - show how and when you load the grid up - that's missing.
Also, why the row created event being used here to setup a event? Just put the event stub and definition in the markup.
You are free to drop in a plane jane button, or DDL or whatever into the GV. And you should wire up the events like all other controls.
So, remove that row created event stub - it might be wiring up events for the wrong row - but it not required, and is a high risk adventure.
So, just do this:
So, for a button, or DDL in the GV? You can't double click on a button (to create a click event), and you can't display the property sheet to add events. But you can in markup just type in the event name, hit "=", and note how above intel-sense pops up a option to create the event. So, add the event that way. And after you select create new event, then you can flip over to code behind - you see the new event stub, and add your code to that stub. The GV uses internal information to wire up each row events - you may well be messing this up.
So, I would remove your row added - as we don't have details about that code and how/when you add a row, but 100% elimination of the row created event, and wiring up a click event will go a long way to elimination of any issues here - this would be especially the case if your row add event "copy's" controls - you might be copy the the DDL object when you do this, and that again will cause issues. In other words you may have the same object for two rows - changes to one will effect the other.
So, dump your row add event, and add the event directly in markup for the ddl as per above.
So, for buttons on each row, or whatever? You can still (and should) use markup to add those events - not code unless no other means exists to do so.
Edit: Working example
So, say this markup:
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
DataKeyNames="ID"
CssClass="table"
Width="30%" OnRowDataBound="GridView1_RowDataBound">
<Columns>
<asp:BoundField DataField="Firstname" HeaderText="Firstname" />
<asp:BoundField DataField="LastName" HeaderText="LastName" />
<asp:TemplateField HeaderText="Select Hotel City">
<ItemTemplate>
<asp:DropDownList ID="cboCity" runat="server" Width="120px" Height="26px"
DataTextField = "City"
DataValueField = "City"
AutoPostback="true"
OnSelectedIndexChanged="cboCity_SelectedIndexChanged"
>
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Select Hotel">
<ItemTemplate>
<asp:DropDownList ID="cboHotels" runat="server" Width="210px" Height="26px"
DataValueField ="ID"
DataTextField ="HotelName">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Nights" >
<ItemTemplate>
<asp:TextBox ID="txtNights" runat="server" Style="text-align:right"
Text='<%# Eval("Nights") %>' Width="70px" >
</asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
We will cascade city combo to restrict Hotels in 2nd combo.
So, our code to load:
DataTable rstCity = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
LoadGrid();
}
void LoadGrid ()
{
// load up City list for combo box - all rows (scope = page)
SqlCommand cmdSQL = new SqlCommand("SELECT City from City ORDER BY City");
rstCity = MyRstP(cmdSQL);
// load up the grid
cmdSQL.CommandText = "SELECT * from People ORDER BY FirstName";
GridView1.DataSource = MyRstP(cmdSQL);
GridView1.DataBind();
}
We have this:
Note how we did NOT risk trying to set the DDL's in the markup - since we cascading - there will be way too many issues.
So, of course we have row data bound - and that sets up the two DDL's. (we setup the cascade AND ALSO set their values.
We have this:
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem; // get the row data
// load the city combo box
DropDownList cboCity = (DropDownList)e.Row.FindControl("cboCity");
cboCity.DataSource = rstCity;
cboCity.DataBind();
// add blank row for city
cboCity.Items.Insert(0, new ListItem("Select City", ""));
cboCity.SelectedValue = gData["City"].ToString(); // set value of Current city
// now load Hotel combo box - but cascade from above City cbo
string strSQL = #"Select ID, HotelName From tblHotels WHERE City = #City " +
" ORDER BY HotelName";
SqlCommand cmdSQL = new SqlCommand(strSQL);
cmdSQL.Parameters.Add("#City", SqlDbType.NVarChar).Value = gData["HotelCity"].ToString();
DropDownList cboHotels = (DropDownList)e.Row.FindControl("cboHotels");
DataTable rstHotels = MyRstP(cmdSQL);
cboHotels.DataSource = rstHotels;
cboHotels.DataBind();
cboHotels.Items.Insert(0, new ListItem("Select Hotel", ""));
// set hotels combo to current selected
cboHotels.SelectedValue = gData["Hotel_id"].ToString();
}
}
So, the only part left is the first DDL post-back and cascade code. We have this:
protected void cboCity_SelectedIndexChanged(object sender, EventArgs e)
{
// city changed, so cascade Hotel cbo
DropDownList cboCity = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)cboCity.NamingContainer;
// filter hotels to current city
string strCity = cboCity.SelectedItem.Text;
DropDownList cboHotels = (DropDownList)gRow.FindControl("cboHotels");
if (strCity != "Select City")
{
SqlCommand cmdSQL = new
SqlCommand(#"SELECT * from tblHotels WHERE City = #City ORDER BY HotelName");
cmdSQL.Parameters.Add("#City", SqlDbType.NVarChar).Value = strCity;
cboHotels.DataSource = MyRstP(cmdSQL);
cboHotels.DataBind();
cboHotels.Items.Insert(0, new ListItem("Select Hotel", ""));
}
}
So, with above? I don't see how it is possible that some "other" row gets effected here (unless you have some other code that attempts to mess around with the rows, or inserts a row into the GV. If you going to insert a row, then insert at the database level - and re-bind the GV. But, inserting is a separate issue.

So here's the update where the second dropdown now functions correctly. However, when you click the update button, it will save correctly to the DB, but resets and clears out the second drowpdown list.
Markup:
<asp:GridView ID="CartList" runat="server" AutoGenerateColumns="False" ShowFooter="True" GridLines="Vertical" CellPadding="4"
ItemType="GetAGrip.Models.CartItem" CssClass="table table-striped table-bordered"
EnableViewState="true">
<Columns>
<asp:BoundField DataField="ProductID" HeaderText="ID" SortExpression="ProductID" />
<asp:BoundField DataField="Product.ProductName" HeaderText="Name" />
<asp:BoundField DataField="Product.UnitPrice" HeaderText="Price (each)" DataFormatString="{0:c}" />
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:TextBox ID="PurchaseQuantity" Width="40" runat="server" Text="<%#: Item.Quantity %>"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Size">
<ItemTemplate>
<asp:DropDownList ID="Sizeddl" runat="server" Font-Size="Medium" OnSelectedIndexChanged="Sizeddl_SelectedIndexChanged"
AutoPostBack="true" ForeColor="Black" SelectedValue="<%#: Item.SizeName %>">
<asp:ListItem Selected="True" Text="Choose one" Value="0"></asp:ListItem>
<asp:ListItem Text="S" Value="S"></asp:ListItem>
<asp:ListItem Text="M" Value="M"></asp:ListItem>
<asp:ListItem Text="L" Value="L"></asp:ListItem>
<asp:ListItem Text="XL" Value="XL"></asp:ListItem>
<asp:ListItem Text="2XL" Value="2XL"></asp:ListItem>
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Color">
<ItemTemplate>
<asp:DropDownList ID="ColorNameddl" runat="server" Font-Size="Medium" ForeColor="Black">
</asp:DropDownList>
<asp:Label ID="Templbl" runat="server" Visible="false" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Item Total">
<ItemTemplate>
<%#: String.Format("{0:c}", ((Convert.ToDouble(Item.Quantity)) * Convert.ToDouble(Item.Product.UnitPrice)))%>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Remove Item">
<ItemTemplate>
<asp:CheckBox ID="Remove" runat="server"></asp:CheckBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<div>
<p></p>
<strong>
<asp:Label ID="LabelSubtotal" runat="server" Text="SubTotal: "></asp:Label>
<asp:Label ID="lblSubtotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTax" runat="server" Text="Tax Total: "></asp:Label>
<asp:Label ID="lblTax" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTotalText" runat="server" Text="Order Total: "></asp:Label>
<asp:Label ID="lblTotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
</div>
<br />
<table>
<tr>
<td>
<asp:Button ID="UpdateBtn" runat="server" Text="Update" OnClick="UpdateBtn_Click" Visible="false" Enabled="false"/>
</td>
<th colspan="1">&nbsp
</th>
<td>
<asp:ImageButton ID="CheckoutImageBtn" runat="server"
ImageUrl="https://www.paypal.com/en_US/i/btn/btn_xpressCheckout.gif"
Width="145" AlternateText="Check out with PayPal"
OnClick="CheckoutBtn_Click"
BackColor="Transparent" BorderWidth="0" />
</td>
</tr>
</table>
Page_Load
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
LoadGrid();
}
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
decimal cartTotal = 0;
cartTotal = usersShoppingCart.GetTotal();
if (cartTotal > 0)
{
// Display Total.
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
}
else
{
lblSubtotal.Text = "";
lblTax.Text = "";
lblTotal.Text = "";
ShoppingCartTitle.InnerText = "Shopping Cart is Empty";
UpdateBtn.Visible = false;
CheckoutImageBtn.Visible = false;
}
}
}
Load Grid, Load Second DropDown List & Hide DDLs on rows they shouldn't be on:
void LoadGrid()
{
GetShoppingCartItems();
CartList.DataSource = GetShoppingCartItems();
CartList.DataBind();
var _db = new ProductContext();
for (int i = 0; i < CartList.Rows.Count; i++)
{
DropDownList sizeDDL = CartList.Rows[i].FindControl("Sizeddl") as DropDownList;
DropDownList colorDDL = CartList.Rows[i].FindControl("ColorNameddl") as DropDownList;
var _colors = (from c in _db.Colors
select c.ColorName).Distinct().ToList();
colorDDL.DataSource = _colors;
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.SelectedIndex = 0;
foreach (ListItem item in colorDDL.Items)
{
item.Attributes.Add("disabled", "disabled");
}
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
var _prodID = Convert.ToInt32(rowValues["ProductID"]);
var _prod = (from c in _db.Products
where c.ProductID == _prodID
select c.CategoryID).FirstOrDefault();
if (_prod != 1)
{
sizeDDL.Visible = false;
colorDDL.Visible = false;
}
}
}
GetShoppingCartItems Method:
public List<CartItem> GetShoppingCartItems()
{
ShoppingCartActions actions = new ShoppingCartActions();
return actions.GetCartItems();
}
UpdateCartItems Method
public List<CartItem> UpdateCartItems()
{
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
String cartId = usersShoppingCart.GetCartId();
ShoppingCartActions.ShoppingCartUpdates[] cartUpdates = new ShoppingCartActions.ShoppingCartUpdates[CartList.Rows.Count];
for (int i = 0; i < CartList.Rows.Count; i++)
{
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
cartUpdates[i].ProductId = Convert.ToInt32(rowValues["ProductID"]);
CheckBox cbRemove = new CheckBox();
cbRemove = (CheckBox)CartList.Rows[i].FindControl("Remove");
cartUpdates[i].RemoveItem = cbRemove.Checked;
TextBox quantityTextBox = new TextBox();
quantityTextBox = (TextBox)CartList.Rows[i].FindControl("PurchaseQuantity");
cartUpdates[i].PurchaseQuantity = Convert.ToInt16(quantityTextBox.Text.ToString());
DropDownList sizeDropDown = new DropDownList();
sizeDropDown = (DropDownList)CartList.Rows[i].FindControl("Sizeddl");
cartUpdates[i].SizeName = sizeDropDown.Text;
DropDownList colorDropDown = new DropDownList();
colorDropDown = (DropDownList)CartList.Rows[i].FindControl("ColorNameddl");
cartUpdates[i].ColorName = colorDropDown.Text;
}
usersShoppingCart.UpdateShoppingCartDatabase(cartId, cartUpdates);
CartList.DataBind();
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
return usersShoppingCart.GetCartItems();
}
}
GetValues Dictionary
public static IOrderedDictionary GetValues(GridViewRow row)
{
IOrderedDictionary values = new OrderedDictionary();
foreach (DataControlFieldCell cell in row.Cells)
{
if (cell.Visible)
{
// Extract values from the cell.
cell.ContainingField.ExtractValuesFromCell(values, cell, row.RowState, true);
}
}
return values;
}
Update Button Click
protected void UpdateBtn_Click(object sender, EventArgs e)
{
for (int i = 0; i < CartList.Rows.Count; i++)
{
UpdateCartItems();
}
Page.Response.Redirect(Page.Request.Url.ToString(), true);
}
RowDataBound
protected void CartList_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem; // get row data.
// load the color Drop Down List.
DropDownList sizeDDL = (DropDownList)e.Row.FindControl("Sizeddl");
sizeDDL.SelectedValue = gData["SizeName"].ToString();
//// Load Color DDL
var _size = sizeDDL.SelectedItem.Text;
int _prod = Convert.ToInt32(e.Row.Cells[0].Text);
var _db = new ProductContext();
var qryColor = (from p in _db.ProductAttributes
join c in _db.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prod
select new { p.ColorID, c.ColorName }).Distinct().ToList();
DropDownList colorDDL = (DropDownList)e.Row.FindControl("ColorNameddl");
// Bind Color Drop Down List to DataTable.
foreach (ListItem item in colorDDL.Items)
{
if (qryColor.Any(c => c.ColorName == item.ToString()))
{
item.Enabled = true;
}
}
colorDDL.SelectedValue = gData["ColorName"].ToString();
}
}
1st Dropdown SelectedIndexChanged
protected void Sizeddl_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList sizeDDL = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)sizeDDL.NamingContainer;
string strSize = sizeDDL.SelectedItem.Text;
DropDownList colorDDL = (DropDownList)gRow.FindControl("ColorNameddl");
if (strSize != "Choose one")
{
using (ProductContext context = new ProductContext())
{
int _prodID = Convert.ToInt32(gRow.Cells[0].Text);
var _size = sizeDDL.SelectedItem.Text;
var qryColor = (from p in context.ProductAttributes
join c in context.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prodID
select new { p.ColorID, c.ColorName }).Distinct().ToList();
if (qryColor.Count > 0)
{
foreach (ListItem item in colorDDL.Items)
{
if (qryColor.Any(c => c.ColorName == item.ToString()))
{
item.Enabled = true;
}
else
{
item.Enabled = false;
}
}
colorDDL.Items[0].Enabled = true;
colorDDL.Enabled = true;
colorDDL.SelectedIndex = 0;
}
else
{
colorDDL.SelectedIndex = 0;
colorDDL.Enabled = false;
}
}
}
}
Anyplace you see a method that is not above, it's because it's a method in my Logic file to handle database queries for the whole application.

c#.net gridview with both (sometimes displayed) button click and row click events

I have a grid with the following definition. I have included two buttons here (different types), but I really only want one, but it must be able to be hidden under certain circumstances.
With the 'ButtonField' I was able to hide it in the RowDataBound event, however, on postback (row click event), all buttons where displayed.
Clicking this button triggers two RowCommand events, one being 'Select' and one being the 'AcceptStats', which would be okay if I could hide the button when not wanted.
The 'asp:Button' displays correctly all the time, but the click event seems to have gotten lost under the row click event.
In the RowCommand event, the CommandName is always 'Select', which comes from the row click event.
I have tried adding OnClick="btnAcceptStats_Click" to the asp:Button, but it doesn't trigger either.
<asp:GridView ID="gvApsimFiles" runat="server" AutoGenerateColumns="false" CssClass="GridViewStyle"
PageSize="10" AllowPaging="true" DataKeyNames="PullRequestId, RunDate"
OnPageIndexChanging="gvApsimFiles_PageIndexChanging"
OnRowCommand="gvApsimFiles_RowCommand"
OnRowDataBound="gvApsimFiles_RowDataBound"
OnSelectedIndexChanged="gvApsimFiles_SelectedIndexChanged" >
<HeaderStyle CssClass="GridViewHeaderStyle" />
<Columns>
<asp:BoundField DataField="PullRequestId" HeaderText="Pull Request Id" ItemStyle-Width="100px" />
<asp:BoundField DataField="RunDate" HtmlEncode="false" HeaderText="Run Date" ItemStyle-Width="220px" DataFormatString="{0:d MMMM, yyyy hh:mm tt}" />
<asp:BoundField DataField="IsMerged" HeaderText="Is Merged" ItemStyle-Width="100px" />
<asp:BoundField DataField="PercentPassed" HtmlEncode="false" HeaderText="Percent<br />Passed" ItemStyle-HorizontalAlign="Right" ItemStyle-Width="100px" />
<asp:BoundField DataField="Total" HeaderText="Total Files" ItemStyle-HorizontalAlign="Right" ItemStyle-Width="100px" />
<asp:ButtonField ButtonType="Button" ItemStyle-Font-Size="11px" Text="Accept Stats" CommandName="AcceptStats" />
<asp:TemplateField>
<ItemTemplate>
<asp:Button ID="btnAcceptStats" runat="server" Text="Accept Stats"
CommandName="AcceptStats"
CommandArgument='<%# Container.DataItemIndex %>'
OnClick="btnAcceptStats_Click"
/>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
In the code behind:
protected void btnAcceptStats_Click(object sender, EventArgs e)
{
GridViewRow gvRow = (GridViewRow)(sender as Control).Parent.Parent;
int index = gvRow.RowIndex;
int pullRequestId = int.Parse(gvApsimFiles.Rows[index].Cells[0].Text);
//Now we can call our web api 'merge' call
bool mergeStatus = bool.Parse(gvApsimFiles.Rows[index].Cells[2].Text);
if (!mergeStatus)
{
UpdatePullRequestMergeStatus(pullRequestId, true);
}
}
protected void gvApsimFiles_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
gvApsimFiles.PageIndex = e.NewPageIndex;
BindApsimFilesGrid();
}
protected void gvApsimFiles_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "AcceptStats")
{
var eVal = Convert.ToInt32(e.CommandArgument);
int index = int.Parse(eVal.ToString());
int pullRequestId = int.Parse(gvApsimFiles.Rows[index].Cells[0].Text);
//Now we can call our web api 'merge' call
bool mergeStatus = bool.Parse(gvApsimFiles.Rows[index].Cells[2].Text);
if (!mergeStatus)
{
UpdatePullRequestMergeStatus(pullRequestId, true);
}
}
}
protected void gvApsimFiles_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
//Show as green if 100%
if (e.Row.Cells[3].Text.Equals("100"))
{
e.Row.ForeColor = Color.Green;
}
//Activate the row click event
e.Row.Attributes["onclick"] = Page.ClientScript.GetPostBackClientHyperlink(gvApsimFiles, "Select$" + e.Row.RowIndex);
e.Row.Attributes["style"] = "cursor:pointer";
}
}
Is there a way that I can have a button, that is only displayed when required, doesn't re-appear on postback, and triggers correctly, while maintaining the row click event?

If you want to hide buttons, why not base their visibility on a value of the GridView inline.
<asp:Button ID="Button2" runat="server" Visible='<%# Convert.ToBoolean(Eval("myBool")) %>' Text="Button 1" />
<asp:Button ID="Button1" runat="server" Visible='<%# !Convert.ToBoolean(Eval("myBool")) %>' Text="Button 2" />

Thanks for your response. I have the asp:Button displaying correctly with the following code:
visible='<%# Eval("IsMerged").ToString().ToLowerInvariant().Equals("false") %>'
The problem is that, when I use this button, I cannot get the Button Click event to work, only the row click event. When I step through the RowCommand the CommandName is only ever 'Select'. I am not able to trigger the 'AcceptStats' event.

I have found a solution. It is through the use of Gridview_RowDataBound, updating each cell in the grid, and then on the Gridview_RowCommand, retrieving these values, and going from there.
It is slightly slower to load, but works. The working code on the .aspx page is as follows:
<asp:GridView ID="gvApsimFiles" runat="server" AutoGenerateColumns="false" CssClass="GridViewStyle"
PageSize="10" AllowPaging="true" DataKeyNames="PullRequestId, RunDate"
OnPageIndexChanging="gvApsimFiles_PageIndexChanging"
OnRowCommand="gvApsimFiles_RowCommand"
OnRowDataBound="gvApsimFiles_RowDataBound" >
<HeaderStyle CssClass="GridViewHeaderStyle" />
<RowStyle CssClass="GridViewRowStyle" />
<Columns>
<asp:BoundField DataField="PullRequestId" HeaderText="Pull Request Id" ItemStyle-Width="100px" />
<asp:BoundField DataField="RunDate" HtmlEncode="false" HeaderText="Run Date" ItemStyle-Width="220px" DataFormatString="{0:d MMMM, yyyy hh:mm tt}" />
<asp:BoundField DataField="IsMerged" HeaderText="Is Merged" ItemStyle-Width="100px" />
<asp:BoundField DataField="PercentPassed" HtmlEncode="false" HeaderText="Percent<br />Passed" ItemStyle-HorizontalAlign="Right" ItemStyle-Width="100px" />
<asp:BoundField DataField="Total" HeaderText="Total Files" ItemStyle-HorizontalAlign="Right" ItemStyle-Width="100px" />
<asp:TemplateField>
<ItemTemplate>
<asp:Button ID="btnAcceptStats" runat="server" Text="Accept Stats"
Visible='<%# Eval("IsMerged").ToString().ToLowerInvariant().Equals("false") %>'
/>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
with the code behind being:
protected void gvApsimFiles_RowCommand(object sender, GridViewCommandEventArgs e)
{
// Don't interfere with other commands.
// We may not have any now, but this is another safe-code strategy.
if (e.CommandName == "CellSelect")
{
// Unpack the arguments.
String[] arguments = ((String)e.CommandArgument).Split(new char[] { ',' });
// More safe coding: Don't assume there are at least 2 arguments.
// (And ignore when there are more.)
if (arguments.Length >= 2)
{
// And even more safe coding: Don't assume the arguments are proper int values.
int rowIndex = -1, cellIndex = -1;
bool canUpdate = false;
int.TryParse(arguments[0], out rowIndex);
int.TryParse(arguments[1], out cellIndex);
bool.TryParse(arguments[2], out canUpdate);
// Use the rowIndex to select the Row, like Select would do.
if (rowIndex > -1 && rowIndex < gvApsimFiles.Rows.Count)
{
gvApsimFiles.SelectedIndex = rowIndex;
}
//here we either update the Update Panel (if the user clicks only anything OTHER THAN our'Button'
//or we process the UpdatePullRequest as Merged
if (cellIndex == 5 && canUpdate == true)
{
int pullRequestId = int.Parse(gvApsimFiles.Rows[rowIndex].Cells[0].Text);
UpdatePullRequestMergeStatus(pullRequestId, true);
}
else
{
int pullRequestId = int.Parse(gvApsimFiles.Rows[rowIndex].Cells[0].Text);
BindSimFilesGrid(pullRequestId);
}
}
}
}
protected void gvApsimFiles_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
//Show as green if 100%
if (e.Row.Cells[3].Text.Equals("100"))
{
e.Row.ForeColor = Color.Green;
}
e.Row.Attributes["style"] = "cursor:pointer";
//Active cell click events on individual cells, instead of the row
foreach (TableCell cell in e.Row.Cells)
{
// Although we already know this should be the case, make safe code. Makes copying for reuse a lot easier.
if (cell is DataControlFieldCell)
{
int cellIndex = e.Row.Cells.GetCellIndex(cell);
bool canUpdate = false;
// if we are binding the 'Button' column, and the "IsMerged' is false, then whe can Update the Merge Status.
if (cellIndex == 5 && e.Row.Cells[2].Text.ToLower().Equals("false"))
{
canUpdate = true;
}
// Put the link on the cell.
cell.Attributes["onclick"] = Page.ClientScript.GetPostBackClientHyperlink(gvApsimFiles, String.Format("CellSelect${0},{1},{2}", e.Row.RowIndex, cellIndex, canUpdate));
// Register for event validation: This will keep ASP from giving nasty errors from getting events from controls that shouldn't be sending any.
Page.ClientScript.RegisterForEventValidation(gvApsimFiles.UniqueID, String.Format("CellSelect${0},{1},{2}", e.Row.RowIndex, cellIndex, canUpdate));
}
}
}
}

Dynamic control Viewstate

I am now stuck. After spending ages trying to maintain dynamically added linkbutton or label to a gridview it seems I am overwriting a checkbox state on post back.
As stated I am dynamically adding either a linkbutton or a label to a place holder in a gridview with the following:
protected void LedgerGrid_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
int index = e.Row.RowIndex;
if (items[index].noteID > 0)
{
PlaceHolder label = (PlaceHolder)e.Row.FindControl("HasPrevious");
LinkButton link = new LinkButton();
link.CommandName = "LinkCommand";
link.Command += new CommandEventHandler(link_Command);
link.Text = "Yes";
link.ID = index.ToString();
label.Controls.Add(link);
}
else
{
PlaceHolder label = (PlaceHolder)e.Row.FindControl("HasPrevious");
Label noNote = new Label();
noNote.Text = "No";
label.Controls.Add(noNote);
}
Here is the gridview:
<asp:GridView runat="server" ID="LedgerGrid" AutoGenerateColumns="false"
onselectedindexchanged="LedgerGrid_SelectedIndexChanged"
onrowdatabound="LedgerGrid_RowDataBound" onrowcommand="LedgerGrid_RowCommand"
>
<Columns>
<asp:TemplateField HeaderText="Notes">
<ItemTemplate>
<asp:PlaceHolder ID="HasPrevious" runat="server"></asp:PlaceHolder>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField HeaderText="Invoice Date" DataField="invoicedate" DataFormatString="{0:d}" />
<asp:BoundField HeaderText="Invoice" DataField="invoice" />
<asp:BoundField HeaderText="Fee Debt" DataField="Fee_Debt" DataFormatString="{0:C}" />
<asp:BoundField HeaderText="Cost Debt" DataField="Cost_Debt" DataFormatString="{0:C}" />
<asp:BoundField HeaderText="VAT Debt" DataField="VAT_Debt" DataFormatString="{0:C}" />
<asp:BoundField HeaderText="Total Debt" DataField="Total_Debt" DataFormatString="{0:C}" />
<asp:BoundField HeaderText="Client Code" DataField="ClientCode" />
<asp:ButtonField HeaderText="Matter Number" DataTextField="matternumber" CommandName="ViewMatter" />
<asp:BoundField HeaderText="Decription" DataField="matterdescription" />
<asp:TemplateField>
<ItemTemplate>
<asp:CheckBox ID="AddInvoiceCheck" runat="server" Enabled="true" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
To make sure that my link button command works I am rebuilding the gridview as I would in the Page_load. Here is the page load:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
string clientCode = Server.HtmlEncode(Request.QueryString["clientcode"]);
items = DataAccess.DataAccess.GetLedgerDetails(clientCode);
ViewState["LedgerItems"] = items;
ViewState["clientcode"] = clientCode;
LedgerGrid.DataSource = items;
LedgerGrid.DataBind();
LedgerClientObject clientDetails = DataAccess.DataAccess.GetClientDetails(clientCode);
ClientCodeLabel.Text = string.Format("Group Code: {0}", clientDetails.GroupCode);
ClientNameLabel.Text = string.Format("Client Name: {0}", clientDetails.ClientName);
ClientCodeFilter.DataSource = clientDetails.ClientCodes;
ClientCodeFilter.DataBind();
}
}
To maintain the dynamically added controls on post back I am calling the following:
protected void Page_PreLoad(object sender, EventArgs e)
{
if (IsPostBack)
{
items = (List<LedgerItem>)ViewState["LedgerItems"];
LedgerGrid.DataSource = items;
LedgerGrid.DataBind();
}
}
Of course it now seems that by using this method I am overwriting the state of the check-box gridview column. Am I approaching this all wrong? I would like to be able to use the viewstate to maintain the set up of my dynamically added controls to the gridview. Is there a way I can access the state of the checkbox control form gridview before/after I reload the gridview in PreLoad event?
I am checking the state of my checkbox column with a button click as follows:
protected void Unnamed1_Click(object sender, EventArgs e)
{
NoteModel note = new NoteModel();
for (int i = 0; i < LedgerGrid.Rows.Count; i++)
{
int invoice = Convert.ToInt32(LedgerGrid.Rows[i].Cells[2].Text);
CheckBox check = (CheckBox)LedgerGrid.Rows[i].FindControl("AddInvoiceCheck");
if (check.Checked)
{
note.invoices.Add(invoice);
}
}
if (note.invoices == null)
{
string clientcode = (string)ViewState["clientcode"];
ViewState["InvoiceError"] = 1;
Response.Redirect(string.Format("Ledger.aspx?clientcode={0}", clientcode));
}
else
{
string clientcode = (string)ViewState["clientcode"];
Session["NoteObject"] = note;
Response.Redirect(string.Format("AddNote.aspx?cc={0}", clientcode));
}
}
Whenever I iterate over the checkbox controls in the gridview they are all unchecked e.g overwritten by my PreLoad code!!!

In the end I decided not to use dynamically created controls. Instead I added a buttonfield to the grid view. In my rowdatabound event I then set the visibility of the button to false if it does meet my criteria. This way view state is maintained as i do not need to create control on post back.
Seems with webforms that avoiding dynamic controls where possible is the best bet. I would still like to know which event to tap into to override viewstate re-instating controls?

Update ASP Label inside ASP Datalist

I have an ASP Datalist with a nested GridView.
I am trying to display an ASP label for each list item where the gridview has more than 6 rows and keep it hidden for those list items where the gridview has < 6 rows.
Here is the datalist:
<asp:DataList runat="server" id="listResponses" DataKeyField="QuestionID" OnItemDataBound="listResponses_ItemDataBound" Width="100%">
<ItemTemplate>
<div class="question_header">
<p><strong><asp:Label ID="lblOrder" runat="server" Text='<%# Container.ItemIndex + 1 %>'></asp:Label>. <%# DataBinder.Eval(Container.DataItem, "QuestionText") %></strong></p>
</div> <!-- end question_header -->
<asp:GridView runat="server" ID="gridResponses" DataKeyNames="AnswerID" AutoGenerateColumns="False" CssClass="responses" AlternatingRowStyle-BackColor="#f3f4f8">
<Columns>
<asp:BoundField DataField="AnswerTitle" HeaderText="Answer Title" HeaderStyle-ForeColor="#717171" ItemStyle-Width="250px"></asp:BoundField>
<asp:BoundField DataField="Responses" HeaderText="Response Count" HeaderStyle-ForeColor="#717171" HeaderStyle-Width="100px" />
<asp:TemplateField>
<ItemTemplate>
<div class="pbcontainer">
<div class="progressbar"></div>
<asp:HiddenField ID="hiddenValue" runat="server" Value='<%# Eval("Responses") %>' />
</div>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<a><asp:Label runat="server" ID="lblShowResponses" Visible="false"></asp:Label></a>
</ItemTemplate>
</asp:DataList>
The label I am trying to update is lblShowResponses.
The method to populate the datalist:
// populate datalist.
DT = GetData.GetQuestionNameDataList(qid);
listResponses.DataSource = DT;
listResponses.DataBind();
And the gridview is populated as follows:
protected void listResponses_ItemDataBound(object sender, DataListItemEventArgs e)
{
GridView gridResponses = (GridView)e.Item.FindControl("gridResponses");
BindGrid(gridResponses, (int)listResponses.DataKeys[e.Item.ItemIndex], DT.Rows[e.Item.ItemIndex][2].ToString());
}
// Get the question ID from the datalist and parse the parameters to BindGrid
protected void listResponses_ItemDataBound(object sender, DataListItemEventArgs e)
{
GridView gridResponses = (GridView)e.Item.FindControl("gridResponses");
BindGrid(gridResponses, (int)listResponses.DataKeys[e.Item.ItemIndex], DT.Rows[e.Item.ItemIndex][2].ToString());
}
private void BindGrid(GridView GridView, int questionId, string questionType)
{
// get the answerID and title for the current question.
DataTable answersDataTable = new DataTable();
answersDataTable = GetData.GetAnswerResponses(questionId);
DataTable tempResponses = new DataTable();
// checkbox question type - loop through each answer and obtain the number of responses.
for (int answer = 0; answer < answersDataTable.Rows.Count; answer++)
{
// populate tempaory datatable and replace DT with the response count.
string answerID = answersDataTable.Rows[answer][0].ToString();
tempResponses = GetData.getIndividualQuestionResponses(questionId, answerID);
answersDataTable.Rows[answer][2] = tempResponses.Rows[0][0];
}
if (GridView.Rows.Count > 6)
{
for (int x = 6; x < GridView.Rows.Count; x++)
{
GridView.Rows[x].Visible = false;
}
// I want to populate the label here!!!!!!
}
}
How can I update/populate the label lblShowResponses when the gridview contains more than 6 rows?

Not sure if this would help you, pass the DataListItemEventArgs param "e" to the BindGrid method and in the location you want to populate the label and use
(e.Item.FindControl("lblShowResponses") as Label).Text = "Test";
(e.Item.FindControl("lblShowResponses") as Label).Visible = true;

ASP.NET GridView, enabling/disabling buttons after paging

I have successfully implemented my GridView now, but, as always, the whole ASP.NET life cycle thing is bothering me. I can't figure out why this doesn't work. I have bound the GridView's OnPageIndexChanged as such:
protected void GridView_PageIndexChanged(object sender, EventArgs e)
{
// Enable/disable the previous/next buttons.
LinkButton btnNextPage = (LinkButton)gvTable.BottomPagerRow.FindControl("btnNextPage");
LinkButton btnPreviousPage = (LinkButton)gvTable.BottomPagerRow.FindControl("btnPreviousPage");
btnNextPage.Enabled = false;
btnPreviousPage.Enabled = false;
}
This is my ASCX:
<asp:GridView ID="gvTable" runat="server" ShowHeader="true" PageSize="1"
AllowPaging="true" AllowSorting="true" DataSourceID="dsLinqActivities"
AutoGenerateColumns="false" OnRowDataBound="GridView_DataBound"
OnPageIndexChanged="GridView_PageIndexChanged">
<Columns>
<asp:BoundField DataField="Edited" HeaderText="Date" />
<asp:BoundField DataField="Status" HeaderText="Status" />
<asp:BoundField DataField="Activity" />
</Columns>
<PagerSettings Position="Bottom" Visible="true" />
<PagerStyle CssClass="pager" />
<PagerTemplate>
<asp:LinkButton ID="btnPreviousPage" class="navbtn prev left"
runat="server" CommandName="Page" CommandArgument="Prev">
<span>Newer activities</span></asp:LinkButton>
<asp:LinkButton ID="btnNextPage" class="navbtn next right"
runat="server" CommandName="Page" CommandArgument="Next">
<span>Older activities</span></asp:LinkButton>
</PagerTemplate>
</asp:GridView>
I debug my application and see that the code is being run and does the right thing but for some reason when the control is rendered, both of the buttons are always enabled. What am I doing wrong here?

If I were you, I would code it like this in the "GridView_PageIndexChanged" method
(gvTable.BottomPagerRow.FindControl("btnNextPage") as LinkButton).Enabled = true/false;
Edit:Can you also try adding a setter ?
set
{
gvTable.BottomPagerRow.FindControl("btnNextPage") as LinkButton =value;
}
Edit: OK my friend, I finally worked out a solution. May be not very elegant,but it works and I tested it. There are a few things to take care of:
1. We are having a "Prev" and a "Next" button and we got to handle "OnCommand" events for those since we are using our own Pager Template
2. We would have to bind data after we handle our OnCommand event.
I have a static List<String> which I populated during GET with random strings (Courtesy: http://www.kivela.be/index.php/2007/06/19/how-to-generate-a-random-string-in-c-20/) and bound them to my grid. You can substitute your own datasource here.Also, we have to change the grid's page index manually in our OnCommand Event.
Here is my aspx/ascx grid
<asp:GridView ID="GridView1" runat="server" OnRowDataBound="GridView_DataBound"
AllowPaging="true" PagerSettings-Mode="NextPrevious" PagerSettings-Position="Bottom" PageSize="10"
OnPageIndexChanged="GridView_PageIndexChanged">
<PagerSettings Position="Bottom" Visible="true" />
<PagerStyle CssClass="pager" />
<PagerTemplate>
<asp:LinkButton ID="btnPreviousPage" OnCommand="ChangePage"
runat="server" CommandName="Prev" Text="prev">
</asp:LinkButton>
<asp:LinkButton ID="btnNextPage" OnCommand="ChangePage"
runat="server" CommandName="Next" Text="next">
</asp:LinkButton>
</PagerTemplate>
</asp:GridView>
and here is the codebehind
public partial class TestPage : System.Web.UI.Page
{
private static Random _random = new Random();
static List<string> lst = new List<string>();
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
for (int i = 1; i <= 30; i++)
{
lst.Add(RandomString(i));
}
GridView1.DataSource = lst;
GridView1.DataBind();
SetPageNumbers();
}
}
private void SetPageNumbers()
{
if (GridView1.PageIndex == 0)
{
(GridView1.BottomPagerRow.FindControl("btnPreviousPage")as LinkButton).Enabled = false;
}
if(GridView1.PageIndex ==GridView1.PageCount-1)
{
(GridView1.BottomPagerRow.FindControl("btnNextPage") as LinkButton).Enabled = false;
}
}
protected void ChangePage(object sender, CommandEventArgs e)
{
switch (e.CommandName)
{
case "Prev":
GridView1.PageIndex = GridView1.PageIndex - 1;
break;
case "Next":
GridView1.PageIndex = GridView1.PageIndex + 1;
break;
}
GridView1.DataSource = lst;
GridView1.DataBind();
SetPageNumbers();
}
public static string RandomString(int size)
{
StringBuilder builder = new StringBuilder();
for (int i = 0; i < size; i++)
{
//26 letters in the alfabet, ascii + 65 for the capital letters
builder.Append(Convert.ToChar(Convert.ToInt32(Math.Floor(26 * _random.NextDouble() + 65))));
}
return builder.ToString();
}
}
Hope this helps

Is there any chance your CSS is setting the enabled property?
I duplicated your code without the CSS and it works fine for me.
How about posting your css?