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How to store value in hyperlink link selected row in gridview asp.net C#?

I have a gridview.I have a hyperlink field and I want that when I click on hyperlink field, then row value is store in session and page redirect to other page. How can I do this?
Here is my aspx markup:
<asp:GridView ID="GridView1" runat="server" Height="36px"
style="margin-left: 270px; margin-top: 92px" Width="232px" CellPadding="3"
BackColor="White" BorderColor="#CCCCCC" BorderStyle="None"
BorderWidth="1px" onrowcancelingedit="GridView1_RowCancelingEdit"
onrowediting="GridView1_RowEditing" onrowupdated="GridView1_RowUpdated"
onrowupdating="GridView1_RowUpdating" AutoGenerateColumns="False"
onrowdeleting="GridView1_RowDeleting">
<Columns>
<asp:TemplateField HeaderText="Table Name">
<EditItemTemplate>
<asp:TextBox ID="txtTBL" runat="server" Text='<%# Eval("Table_Name") %>'></asp:TextBox>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label1" runat="server" Text='<%# Eval("Table_Name") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:CommandField HeaderText="Operation" ShowEditButton="True"
ShowDeleteButton="True" />
<asp:TemplateField>
<ItemTemplate>
<asp:HyperLink Text="Select" ID="lnkSelect" runat="server" CommandName="Select" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
<FooterStyle BackColor="White" ForeColor="#000066" />
<HeaderStyle BackColor="#006699" Font-Bold="True" ForeColor="White" />
<PagerStyle BackColor="White" ForeColor="#000066" HorizontalAlign="Left" />
<RowStyle ForeColor="#000066" />
<SelectedRowStyle BackColor="#669999" Font-Bold="True" ForeColor="White" />
<SortedAscendingCellStyle BackColor="#F1F1F1" />
<SortedAscendingHeaderStyle BackColor="#007DBB" />
<SortedDescendingCellStyle BackColor="#CAC9C9" />
<SortedDescendingHeaderStyle BackColor="#00547E" />
</asp:GridView>
And here is my code behind :
public partial class DisplayTable : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
// Retrieve database gridview
gettable();
}
}
public void gettable()
{
// here is code
}
//here all code included regarding to edit,delete etc
protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
string s = ((HyperLink)GridView1.SelectedRow.Cells[0].Controls[0]).Text;
Session["destype"] = s;
Page.Response.Redirect("home.aspx");
}
public override void VerifyRenderingInServerForm(Control control)
{
// base.VerifyRenderingInServerForm(control);
}
}

Hope following will work for you, Not sure as not tested by me.
protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
GridViewRow gr = ((sender as HyperLink).NamingContainer as GridViewRow);
Session["destype"] = gr.Cells[0].Text.Trim(); /*For first cell value of Row */
//Session["abc"] = gr.Cells[2].Text.Trim(); /*Repeat for other cell values of Row by increasing cell index */
Response.Redirect("~/home.aspx");
}
Also have look on Send (Pass) GridView Row Values to next page using Session variable in ASP.Net

I've never been a fan of accessing information by cell reference when it comes from a backing store like a database.
There are a number of ways to accomplish this. I prefer making the information available to the link button.
In your markup you can do this:
<ItemTemplate>
<asp:LinkButton Text="Select" ID="lnkSelect" runat="server"
data-tablename='<%# Eval("Table_Name") %>'
CommandName="Select"
// And consider doing this as often as needed
// It should be self evident :)
CommandArgument="<%# ((GridViewRow) Container).RowIndex %>"
/>
</ItemTemplate>
or equivalently, in the RowDatabound Event:
protected void GridView1_RowDataBound( object sender, GridViewRowEventArgs e ) {
if ( e.Row.RowType == DataControlRowType.DataRow ) {
DataRowView drv = (DataRowView) e.Row.DataItem ;
LinkButton lnkSelect = (LinkButton) e.Row.FindControl("lnkSelect");
lnkSelect.Attributes["data-tablename"] = drv["Table_Name"];
}
}
then in SelectedIndexChanged
protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
GridView gv = (GridView) sender;
LinkButton lnkSelect = ( LinkButton ) gv.Rows[ gv.SelectedIndex ].FindControl( "lnkSelect" );
Session[ "destype" ] = lnkSelect.Attributes[ "data-tablename" ];
Page.Response.Redirect("home.aspx");
}
or in RowCommand
protected void GridView1_RowCommand( object sender, GridViewCommandEventArgs e ) {
if ( e.CommandName == "Select" ) {
LinkButton lnkSelect = ( LinkButton ) e.CommandSource;
Session[ "destype" ] = lnkSelect.Attributes[ "data-tablename" ];
Page.Response.Redirect("home.aspx");
}
}
Addendum
NOTE: Hyperlinks are not reliable if you do not provide an href. Since you need to postback first before redirecting to home.aspx, change the HyperLink to a LinkButton. I've revised my entire answer accordingly.
In the aspx markup, modify the hyperlink with this:
<ItemTemplate>
<asp:LinkButton ID="lnkSelect" runat="server"
Text="Select"
CommandName="Select"
data-tablename='<%# Eval("Table_Name") %>' />
</ItemTemplate>
And in SelectedIndexChanged do this
protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
GridView gv = (GridView) sender;
LinkButton lnkSelect = ( LinkButton ) gv.Rows[ gv.SelectedIndex ].FindControl( "lnkSelect" );
Session[ "destype" ] = (string) lnkSelect.Attributes[ "data-tablename" ];
Page.Response.Redirect("home.aspx");
}

OnRowUpdating Does not take value of edit template textbox

I am trying to update a value in my gridview on row updating. However, it refuses to take in the value written in the textbox. I populate the gridview if the page is not post back. Help!
GRIDVIEW:
<asp:UpdatePanel runat="server" UpdateMode=Conditional><ContentTemplate>
<asp:GridView runat="server" ID="searchGV" AutoGenerateColumns="False" GridLines="None"
CssClass="mGrid" EmptyDataText="The Search Did Not Return Any Results"
PagerStyle-CssClass="pgr" AlternatingRowStyle-CssClass="alt" Width="100%" OnRowCancelingEdit="searchGV_RowCancelingEdit"
OnRowEditing="searchGV_RowEditing" DataKeyNames="media_id" OnRowUpdating="searchGV_RowUpdating">
<Columns>
<asp:BoundField DataField="media_id" Visible="false" HeaderText="" />
<asp:BoundField DataField="dir_path" Visible="false" HeaderText="Dir" />
<asp:TemplateField HeaderText="Date Taken" >
<ItemTemplate>
<asp:LinkButton ID="dateLinkCsBtn" OnClientClick='<%#Eval("dir_path","Javascript:return test(\"{0}\",event);")%>'
runat="server" Text='<%# Bind("date") %>'></asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Media Type">
<ItemTemplate>
<asp:Label runat="server" ID="mediaTypeLbl" Text='<%#Eval("description") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Alias File Name">
<ItemTemplate>
<asp:Label runat="server" ID="aliasFileName" Text='<%#Bind("alias_file_name") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:TextBox runat="server" Text='<%#Bind("alias_file_name") %>' ID="updateAliasTxt"></asp:TextBox>
</EditItemTemplate>
</asp:TemplateField>
<asp:CommandField ShowEditButton="True" />
</Columns>
</asp:GridView>
</ContentTemplate></asp:UpdatePanel>
CODE BEHIND:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
FillGrid();
}
}
protected void searchGV_RowEditing(object sender, GridViewEditEventArgs e)
{
searchGV.EditIndex = e.NewEditIndex;
FillGrid();
}
protected void searchGV_RowCancelingEdit(object sender,
GridViewCancelEditEventArgs e)
{
searchGV.EditIndex = -1;
FillGrid();
}
public void FillGrid()
{
Media_DAO media_query = new Media_DAO();
searchGV.DataSource = media_query.get_search_media(alias_file_name_txt.Text.Trim(), Convert.ToInt16(mediaTypeDDL.SelectedValue),
from_date_txt.Text.Trim(), to_date_txt.Text.Trim(), Convert.ToInt16(Session["user_id"]));
searchGV.DataBind();
}
protected void searchGV_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
GridViewRow row = searchGV.Rows[e.RowIndex];
TextBox new_alias = (TextBox)searchGV.Rows[e.RowIndex].FindControl("updateAliasTxt");
int media_id = Convert.ToInt16(searchGV.DataKeys[e.RowIndex]["media_id"]);
Media_DAO media_query2 = new Media_DAO();
media_query2.update_alias_name_by_id(media_id, new_alias.Text.Trim(), Convert.ToInt16(Session["user_id"]));
searchGV.EditIndex = -1;
FillGrid();
}

while declaring the grid you have specified only 1 *data key value*
asDataKeyNames="media_id"
DateKeys for grid view is stored in array format starting from 0.
The error may be in getting the media_id while updating. You need to change it as follows.
protected void searchGV_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
GridViewRow row = searchGV.Rows[e.RowIndex];
TextBox new_alias = (TextBox)searchGV.Rows[e.RowIndex].FindControl("updateAliasTxt");
int media_id = Convert.ToInt16(e.Keys[0]); //this will get the media_id
Media_DAO media_query2 = new Media_DAO();
media_query2.update_alias_name_by_id(media_id, new_alias.Text.Trim(), Convert.ToInt16(Session["user_id"]));
searchGV.EditIndex = -1;
FillGrid();
}
Since the earlier method was searchGV.DataKeys[e.RowIndex]["media_id"] , you might not get the media_id value if the row number which you are trying to edit is greater than 1.

The DataKeys property of GridView returns a collection of DataKey objects that represents the data key value of each row for a GridView. Thus, DataKeys[1] gives 2nd row, DataKeys[4] gives 5th row ...
Therefore, you need to use either the Value OR the Values property to access the value of a key field.
Rather than doing this:
int media_id = Convert.ToInt16(searchGV.DataKeys[e.RowIndex]["media_id"]);
do this:
int media_id = Convert.ToInt16(searchGV.DataKeys[e.RowIndex].Values["media_id"]);
// You can also use the Value property which gives the key value at index 0
int media_id = Convert.ToInt16(searchGV.DataKeys[e.RowIndex].Value);

ADO.net Entity Gridview is null when RowUpdating event fired

So I'm using ADO.net Entity Data model in an ASP.Net (C#) Web page. I am dynamically adding and retrieving data to my database using gridviews. I am using master pages, and my gridview is in a contentplaceholder. My only issue with this code is that when my RowUpdating event fires, the gridview is null. I can call by BindGV function, and then the rest of the code updates the database perfectly fine, with the original data from the database I just bound to it, since the database was not updated yet. In all events, if I change bindGV() to Gridview1.databind(), the gridview is null. I think the datasource the gridview is referencing is becoming null at the end of the event when the data connection is closed, is there anyway to prevent this?
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
onrowcancelingedit="GridView1_RowCancelingEdit"
onrowediting="GridView1_RowEditing" onrowupdating="GridView1_RowUpdating"
onrowdatabound="GridView1_RowDataBound"
>
<Columns>
<asp:TemplateField Visible="false">
<ItemTemplate>
<asp:Label ID="lblId" runat="server" Text='<%# Eval("id") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:Label ID="lblId" runat="server" Text='<%# Eval("id") %>'></asp:Label>
</EditItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Machine">
<ItemTemplate>
<asp:Label ID="lblMachine" runat="server" Text='<%# Eval("MachineName") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:TextBox ID="txtMachine" runat="server" Text='<%# Eval("MachineName") %>'></asp:TextBox>
</EditItemTemplate>
<ControlStyle Width="60px" />
</asp:TemplateField>
<asp:TemplateField HeaderText="Dept">
<ItemTemplate>
<asp:Label ID="lblDept" runat="server" Text='<%# Eval("WorkCenterFK") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:DropDownList ID="ddldept" runat="server" >
</asp:DropDownList>
</EditItemTemplate>
<ControlStyle Width="120px" />
</asp:TemplateField>
<asp:CommandField HeaderText="Actions" ShowEditButton="true" ShowDeleteButton="True"
ControlStyle-Width="50px" CausesValidation="false">
</asp:CommandField>
</Columns>
protected void BindGV()
{
QualityEntities database = new QualityEntities();
GridView1.DataSource = (from m in database.Machines
from d in database.Workcenters
where m.WorkcenterFK == d.id
select
new { id = m.id, MachineName = m.MachineName, WorkCenterFK = d.WorkCenterName }); ;
GridView1.DataBind();
}
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack) BindGV();
}
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
BindGV();
}
protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
{
GridView1.EditIndex = -1;
BindGV();
}
protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
QualityEntities database = new QualityEntities();
BindGV();
Int32 id = Convert.ToInt32(((Label)GridView1.Rows[e.RowIndex].FindControl("lblId")).Text);
DropDownList ddl = ((DropDownList)GridView1.Rows[e.RowIndex].FindControl("ddlDept"));
TextBox txt = ((TextBox)GridView1.Rows[e.RowIndex].FindControl("txtMachine"));
Machine mch = (from m in database.Machines where m.id == id select m).Single();
mch.MachineName = txt.Text;
mch.WorkcenterFK = Convert.ToInt32(ddl.SelectedItem.Value);
database.SaveChanges();
GridView1.EditIndex = -1;
BindGV();
}
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
QualityEntities database = new QualityEntities();
DropDownList temp = (DropDownList)(e.Row.FindControl("ddlDept"));
if (temp != null)
{
temp.DataSource = (from w in database.Workcenters select w);
temp.DataTextField = "WorkCenterName";
temp.DataValueField = "id";
temp.DataBind();
Int32 id = Convert.ToInt32(((Label)e.Row.FindControl("lblId")).Text);
}
}

Not sure why the GridView is null, but instead of using a member variable i would use the sender of the event which is always the source of the event (in this case the GridView)
// ...
GridView grid = (GridView)sender;
Int32 id = Convert.ToInt32(((Label)grid.Rows[e.RowIndex].FindControl("lblId")).Text);
// ...

Changing button text of gridview

I have a grid view which contains a button in a template field. I want to change the button text when the button click event is completed. Can somebody send me a sample code.
Thanks in advance

Here is a sample bit of code using the RowCommand() of the GridView.
ASPX
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" onrowcommand="GridView1_RowCommand">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:Label ID="lbl1" runat="server"></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<asp:Button ID="Button1" runat="server" CausesValidation="false" CommandName="MYCOMMAND" Text="My Text!" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
C#
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
List<string> lst = new List<string>() { "asd", "xxx" };
GridView1.DataSource = lst;
GridView1.DataBind();
}
}
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "MYCOMMAND")
{
Button Button1 = (Button)e.CommandSource;
if (Button1 != null)
Button1.Text = "changed text..";
}
}

C# Question About Delete Data Grid

I have binded a data grid to an array. Also, there is a button there to delete the row. The problem is that I am not sure how to implement it since the data source is an array.
See below
<Columns>
<asp:TemplateColumn>
<ItemTemplate>
<asp:Label ID="lblItems" runat="server" Text='<%# Container.DataItem>' />
</ItemTemplate>
</asp:TemplateColumn>
<asp:ButtonColumn ButtonType="PushButton" CommandName="Delete" Text="Delete">
</asp:ButtonColumn>
</Columns>
and here I would like to implement it..
private void DataGrid1_DeleteCommand(object source,
System.Web.UI.WebControls.DataGridCommandEventArgs e)
{
int rowToDelete = e.Item.ItemIndex;
myDataGrid.DataBind();
}
In the code for the deletion, how can I access the index of my array based on the button clicked (per row)?

Here is an example
Markup.
<asp:DataGrid ID="DataGrid1" runat="server"
AutoGenerateColumns="False"
OnDeleteCommand="DataGrid1_DeleteCommand">
<Columns>
<asp:TemplateColumn HeaderText="Name">
<ItemTemplate>
<asp:Label ID="lblItems" runat="server"
Text='<%# Container.DataItem %>'>
</asp:Label>
</ItemTemplate>
</asp:TemplateColumn>
<asp:ButtonColumn ButtonType="PushButton"
CommandName="Delete"
HeaderText="Actions"
Text="Delete">
</asp:ButtonColumn>
</Columns>
</asp:DataGrid>
Code-behind.
private static string[] names = new string[] { "Matt", "Joanne", "Robert" };
protected void Page_Load(object sender, EventArgs e)
{
if(!IsPostBack)
{
BindGrid();
}
}
private void BindGrid()
{
DataGrid1.DataSource = names;
DataGrid1.DataBind();
}
protected void DataGrid1_DeleteCommand(object source, DataGridCommandEventArgs e)
{
string deletedItem = ((Label) DataGrid1.Items[e.Item.ItemIndex].FindControl("lblItems")).Text;
names = names.Where(val => val != deletedItem).ToArray();
BindGrid();
}
Hope this helps.

Have you tried to access your src object using the method below (notice this is 'RowDeleting' event on gridview)?
protected void gv_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
MyObject o = (MyObject)gv.Rows[e.RowIndex].DataItem;
}
There are also other tricks like storing an id in a hiddenfield on the row and then on the delete command you search for the control and pluck your value. My preference is the method above but really depends on what your goal is.
protected void gv_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
HiddenField field = (HiddenField)gv.Rows[e.RowIndex].FindControl("myHiddenField");
string myValue = field.Value;
// delete it and rebind
}