Develop Reference

How can I find a BoundField inside a GridView by DataField?

I want to change the CSS class behind the tenth BoundField inside my GridView, but I'd like to find it by DataField (i.e., use a string as index).
protected void gdDeliveryDates_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
string DeliveryDue = DataBinder.Eval(e.Row.DataItem, "DeliveryDue").ToString();
((LinkButton) e.Row.FindControl("PostDelivery")).Enabled = !String.IsNullOrEmpty(DeliveryDue);
//e.Row.Cells[9].CssClass= "badge";
}
}
In the code above I have commented out the only solution I've found so far, which to me is unacceptable because a column number (i.e., column 9 as specified above) is very volatile. I would prefer to find the column by DataField (a string, in this case, "MailCount" as you'll see in the grid declaration further ahead). Below is what my grid looks like:
<asp:GridView ID="gdDeliveryDates" runat="server" AllowPaging="False" AllowSorting="True" DataSourceID="odsDeliveryDates" AutoGenerateColumns="False" CssClass="table table-striped table-bordered table-hover" OnRowCommand="gdDeliveryDates_RowCommand" OnSelectedIndexChanged="gdDeliveryDates_SelectedIndexChanged" DataKeyNames="PackageOfferedID, PackageID, PostageID, PackageNumber, PackageTitle, PostageName, Section, PostageStart, PostageEnd, DeliveryDue, LName, MailCount, Location" OnRowDataBound="gdDeliveryDates_RowDataBound" >
<Columns>
<asp:BoundField DataField="PackageID" HeaderText="PackageID" Visible="False" ReadOnly="True" SortExpression="PackageID" />
<asp:BoundField DataField="PackageOfferedID" HeaderText="PackageOfferedID" Visible="False" ReadOnly="True" SortExpression="PackageOfferedID" />
<asp:BoundField DataField="PostageID" HeaderText="PostageID" Visible="False" ReadOnly="True" SortExpression="PostageID" />
<asp:BoundField DataField="PackageNumber" HeaderText="Package" Visible="True" ReadOnly="True" SortExpression="PackageNumber" HeaderStyle-CssClass="visible-xs visible-sm visible-md visible-lg" ItemStyle-CssClass="visible-xs visible-sm visible-md visible-lg" />
<asp:BoundField DataField="PostageName" HeaderText="Postage" ReadOnly="True" SortExpression="PostageName" HeaderStyle-CssClass="visible-sm visible-md visible-lg" ItemStyle-CssClass="visible-sm visible-md visible-lg"/>
<asp:BoundField DataField="Section" HeaderText="Section" ReadOnly="True" SortExpression="Section" HeaderStyle-CssClass="visible-xs visible-sm visible-md visible-lg" ItemStyle-CssClass="visible-xs visible-sm visible-md visible-lg" />
<asp:BoundField DataField="PostageStartDate" HeaderText="Start Date" ReadOnly="True" SortExpression="PostageStartDate" DataFormatString="{0:MM/dd/yyyy}" HeaderStyle-CssClass="visible-md visible-lg" ItemStyle-CssClass="visible-md visible-lg" />
<asp:BoundField DataField="PostageEndDate" HeaderText="End Date" ReadOnly="True" SortExpression="PostageEndDate" DataFormatString="{0:MM/dd/yyyy}" HeaderStyle-CssClass="visible-md visible-lg" ItemStyle-CssClass="visible-md visible-lg" />
<asp:BoundField DataField="DeliveryDueDate" HeaderText="Delivery Due" ReadOnly="True" SortExpression="DeliveryDueDate" DataFormatString="{0:MM/dd/yyyy}" HeaderStyle-CssClass="visible-xs visible-sm visible-md visible-lg" ItemStyle-CssClass="visible-xs visible-sm visible-md visible-lg" />
<asp:BoundField DataField="MailCount" HeaderText="#" Visible="True" ReadOnly="True" SortExpression="MailCount" HeaderStyle-CssClass="visible-lg" ItemStyle-CssClass="visible-lg" />
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<asp:LinkButton ID="PostDelivery" runat="server" CausesValidation="false" CommandName="Add"
Text="Post Delivery" CommandArgument='<%# DataBinder.Eval(Container, "RowIndex") %>'
CssClass="buttonLayout" />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="LName" HeaderText="LName" Visible="False" ReadOnly="True" SortExpression="LName" />
<asp:BoundField DataField="Location" HeaderText="Location" Visible="False" ReadOnly="True" SortExpression="Location" />
</Columns>
</asp:GridView>

This is not possible but you can try this method:
public int FindIndexByDataField(this GridView gv, string datafieldname)
{
int index = -1, cnum = 0;
foreach (DataControlField col in gv.Columns)
{
if (col is BoundField)
{
BoundField coll = (BoundField)gv.Columns[cnum];
if (coll.DataField == datafieldname)
{
index = cnum;
break;
}
}
cnum++;
}
return index;
}
And call above method like this:
e.Row.Cells[FindIndexByDataField("MailCount")].CssClass= "badge";

Disabling ButtonField when BoundField is zero

I have this GridView that fills on the Page_Load:
protected void Page_Load(object sender, EventArgs e) {
if (!Page.IsPostBack) {
GridView1.DataSource = actBO.BuscarActividades();
GridView1.DataBind();
}
}
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" >
<Columns>
<asp:BoundField DataField="Id" HeaderText="ID" Visible="False" />
<asp:BoundField DataField="Class" HeaderText="Class" />
<asp:BoundField DataField="Day" HeaderText="Day" />
<asp:BoundField DataField="Time" HeaderText="Time" />
<asp:BoundField DataField="Vacants" HeaderText="Vacants" />
<asp:ButtonField ButtonType="Button" HeaderText="Book" Text="Book"/>
</Columns>
</asp:GridView>
Where column "Vacants" shows an int (it represents the amount of vacant booking spaces in a class).
Every row will have a button to book a specific class. I need to place a condition for when the field "Vacants" is zero, so the "Book" button will be disabled.
So far this is what it looks like: image.
As you can see, I need the button to be disabled when there are no more vacants. It shouldn't be able to be clicked.

To do so, you must register OnRowDataBound event. More explanations can be found in here.
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" OnRowDataBound="GridView1_RowDataBound">
<Columns>
<asp:BoundField DataField="Id" HeaderText="ID" Visible="False" />
<asp:BoundField DataField="Class" HeaderText="Class" />
<asp:BoundField DataField="Day" HeaderText="Day" />
<asp:BoundField DataField="Time" HeaderText="Time" />
<asp:BoundField DataField="Vacants" HeaderText="Vacants" />
<asp:ButtonField ButtonType="Button" HeaderText="Book" Text="Book"/>
</Columns>
</asp:GridView>
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
// get your button via the column index; ideally you could use template field and put your own button inside
var button = e.Row.Cell[5].Controls[0] as Button;
int vacant = 0;
var vacantVal = int.TryParse(e.Row.Cell[4].Text, out vacant);
if (button != null)
{
button.Enabled = vacant > 0;
}
}
}
Hope it helps.

Not able to access hyperlink column inside gridview from code behind

I want to access the HyperLinkField column of the GridView from code behind but I am unable to do so.
I have the column in my dataset but I am still not able to use it.
My HyperLinkField column is named Status.
Here is what I tried:
UltraWebGrid1.DataSource = ObjPriDsGrid;
UltraWebGrid1.DataBind();
string StrPriStatus = "";
for (int IntPriI = 0; IntPriI < UltraWebGrid1.Rows.Count; IntPriI++)
{
if (UltraWebGrid1.Rows[IntPriI].Cells[6].Text.Trim() != null)
{
StrPriStatus = UltraWebGrid1.Rows[IntPriI].Cells[6].Text.Trim();
}
else
{
}
if (StrPriStatus == "5")
{
UltraWebGrid1.Rows[IntPriI].Cells[8].Text = ""; // Not getting status column here
}
}
Here is my GridView:
<asp:GridView ID="UltraWebGrid1" ShowHeader="true" runat="server" AutoGenerateColumns="false"
DataKeyNames="mkey" OnRowDataBound="Grid_RowDataBound" Width="98%" Height="30%"
PageSize="10" AllowPaging="true" OnPageIndexChanging="Grid1_PageIndexChanging"
ShowFooter="true" CssClass="Grid">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<img alt="" style="cursor: pointer" src="../../../Images/plus.png" />
<asp:Panel ID="pnlGrid" runat="server" Style="display: none">
<asp:GridView ID="Grid2" runat="server" AutoGenerateColumns="false" Width="600px"
CssClass="ChildGrid">
<Columns>
<asp:BoundField ItemStyle-Width="80px" DataField="RefMkey" HeaderText="Mkey" />
<asp:BoundField ItemStyle-Width="150px" DataField="CurrentUser" HeaderText="Current User" />
<asp:BoundField ItemStyle-Width="180px" DataField="Department" HeaderText="Current Department" />
<asp:BoundField ItemStyle-Width="100px" DataField="remarks" HeaderText="Remarks" />
</Columns>
</asp:GridView>
</asp:Panel>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField ItemStyle-Width="0px" DataField="mkey" Visible="false" HeaderText="Mkey" />
<asp:BoundField ItemStyle-Width="8%" DataField="Doc_No" HeaderText="IW/ No" />
<asp:BoundField ItemStyle-Width="10%" DataField="Doc_Date" HeaderText="IW/ Date" />
<asp:BoundField ItemStyle-Width="12%" DataField="DocType" HeaderText="Doc type" />
<asp:BoundField ItemStyle-Width="15%" DataField="Party_Name" HeaderText="Party Name" />
<asp:BoundField ItemStyle-Width="0" Visible="true" DataField="Status_Flag" HeaderText="Status" />
<asp:BoundField ItemStyle-Width="10%" DataField="LastAction_datetime" HeaderText="Last Action Date" />
<asp:BoundField ItemStyle-Width="10%" DataField="CurrStatus" HeaderText="Current Status" />
<asp:BoundField ItemStyle-Width="10%" DataField="Type_desc" HeaderText="Resp Dept" />
<asp:BoundField ItemStyle-Width="12%" DataField="UserName" HeaderText="Resp User" />
<asp:BoundField ItemStyle-Width="8%" DataField="No_Of_Days" HeaderText="No of days" />
<asp:HyperLinkField ItemStyle-Width="5%" DataNavigateUrlFields="Mkey, Status, Doc_No"
DataNavigateUrlFormatString="~/Administration/Dispatch/Inward/FrmInwardNextAction.aspx?Inward_mkey={0}&Status={0}&IWNO={0}"
HeaderText="Status" DataTextField="Status" Target="_blank" />
<asp:HyperLinkField ItemStyle-Width="5%" DataNavigateUrlFields="Mkey, Status, Doc_No"
HeaderText="View" DataTextField="View" Target="_blank" DataNavigateUrlFormatString="~/Administration/Dispatch/Inward/InwardDocDetails.aspx?Key={0}&Status={0}&IWNO={0}" />
</Columns>
</asp:GridView>

Columns like HyperLinkField and CheckBoxField behave a little differently than BoundField. They don't just simply contain text like BoundField. You have to get the control within the cell. You can get the child controls of the cell using the Controls collection. We know that specifically for a HyperLinkField, the HyperLink will be the first control in the collection.
HyperLink hyp = (HyperLink)UltraWebGrid1.Rows[IntPriI].Cells[12].Controls[0];

Can you try it like this
if (StrPriStatus == "5")
{
HyperLink HyperLinkObj = (HyperLink)UltraWebGrid1.Rows[IntPriI].Cells[12].Controls[0];
HyperLinkObj.Text = "";
}

Value from row with DropDownList on DropDownList Index Changed Event

Code:
<asp:GridView ID="gv_Recruit" AutoGenerateColumns="False" Width="100%"
runat="server" OnRowCreated="gvStates_RowCreated"
OnRowDataBound="gvStates_RowCreated">
<Columns>
<asp:BoundField HeaderText="key" DataField="key" />
<asp:BoundField HeaderText="Name" DataField="Name" />
<asp:BoundField HeaderText="Quota" DataField="Quota" />
<asp:BoundField HeaderText="Session" DataField="Sess" >
<ItemStyle HorizontalAlign="Center" />
</asp:BoundField>
<asp:TemplateField HeaderText="">
<ItemTemplate>
<asp:DropDownList ID="ddlCities" Width="100%" AutoPostBack="true" runat="server" OnSelectedIndexChanged="ddl_selected">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField HeaderText="Recruiter" DataField="Recruiter" />
<asp:BoundField HeaderText="MN Phone" DataField="MN Phone" />
<asp:BoundField HeaderText="Cell Phone" DataField="Cell Phone" />
</Columns>
</asp:GridView>
Code Behind:
protected void ddl_selected(object sender, EventArgs e)
{
string _dd_value = ((DropDownList)sender).SelectedValue;
string trying_to_get = gv_Recruit.Rows[???].Cells[0].Text.ToString();
string also_tried = gv_Recruit.SelectedRow.Cells[0].Text.ToString();
}
Basically what I'm trying to do is get the key value from the first row when the drop down is changed so I can perform an update ???
Can't figure this out.
Thanks in advance for the help...

Try
GridViewRow gRow = (GridViewRow)(sender as Control).Parent.Parent;
string trying_to_get = string.Empty;
if (gRow != null)
{
trying_to_get = gRow.Cells[0].Text;
}

asp.net Gridview: buttons accessing data for each row

I'm trying to code a Gridview that has a button on each row that when clicked will expose that particular rows data for use, but I'm not sure how the data would be passed.
The Gridview:
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="ID"
DataSourceID="SqlDataSource2">
<Columns>
<asp:BoundField DataField="ID" HeaderText="ID" InsertVisible="False" ReadOnly="True"
SortExpression="ID" Visible="False" />
<asp:BoundField DataField="RelationID" HeaderText="RelationID" InsertVisible="False"
SortExpression="RelationID" Visible="False" />
<asp:BoundField DataField="UserRole" HeaderText="UserRole" InsertVisible="False"
SortExpression="UserRole" Visible="False" />
<asp:BoundField DataField="FirstName" HeaderText="First Name" SortExpression="FirstName" />
<asp:BoundField DataField="Surname" HeaderText="Surname" SortExpression="Surname" />
<asp:BoundField DataField="Telephone" HeaderText="Telephone" SortExpression="Telephone" />
<asp:BoundField DataField="Email" HeaderText="Email" SortExpression="Email" />
<asp:BoundField DataField="Hash" HeaderText="Hash" InsertVisible="False" SortExpression="Hash"
Visible="False" />
<asp:BoundField DataField="DateCreated" HeaderText="Date Invited" SortExpression="DateCreated" />
<asp:TemplateField HeaderText="Resend Welcome Email">
<ItemTemplate>
<asp:Button runat="server" ID="btnResend" Text="Resend" OnClick="btnResend_Click" />
</ItemTemplate>
<ItemStyle HorizontalAlign="Center" VerticalAlign="Middle" />
</asp:TemplateField>
</Columns>
</asp:GridView>
The button_OnClick
protected void btnResend_Click(object sender, EventArgs e)
{
bool boolEmailSent = Email.sendWelcomeEmail(//Email from Row, //FirstName from Row, //Surname from Row, //Hash from Row);
if (boolEmailSent == true)
{
//Confirm to User
}
else
{
//TODO: write error to log
}
}

This article covers what you're attempting in more depth than we could answer here:
http://authors.aspalliance.com/aspxtreme/webforms/controls/addingbuttonfieldstoGridView.aspx
And here's another:
http://msdn.microsoft.com/en-us/library/bb907626.aspx