Get clicked cell index in gridview (not datagridview) asp.net

Question

When I click cell in gridview (not datagridview) I want to get cell index (not row index), not row index. I use asp.net - c#

Answer 1

Use the RowCreated event to register a cell-click on each cell and handle the GridView's SelectedIndexChangedEvent:

protected void OnRowCreated(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        for (int i = 0; i < e.Row.Cells.Count; i++ )
        {
            TableCell cell = e.Row.Cells[i];
            cell.Attributes["onmouseover"] = "this.style.cursor='pointer';this.style.textDecoration='underline';";
            cell.Attributes["onmouseout"] = "this.style.textDecoration='none';";
            cell.ToolTip = "You can click this cell";
            cell.Attributes["onclick"] = string.Format("document.getElementById('{0}').value = {1}; {2}"
               , SelectedGridCellIndex.ClientID, i
               , Page.ClientScript.GetPostBackClientHyperlink((GridView)sender, string.Format("Select${0}", e.Row.RowIndex)));
        }
    }
}

protected void SelectedIndexChanged( Object sender, EventArgs e)
{
    var grid = (GridView) sender;
    GridViewRow selectedRow = grid.SelectedRow;
    int rowIndex = grid.SelectedIndex;
    int selectedCellIndex = int.Parse(this.SelectedGridCellIndex.Value);
}

SelectedGridCellIndex is a hidden-field which is added declaratively on the aspx to store the selected index:

<asp:HiddenField ID="SelectedGridCellIndex" runat="server" Value="-1" />
<asp:GridView ID="GridView1" runat="server" 
    OnRowCreated="OnRowCreated" 
    OnSelectedIndexChanged="SelectedIndexChanged" 
    OnRowDataBound="OnRowDataBound" AutoGenerateColumns="false">
   <Columns>
     .....

You need to disable event-validation for this page, otherwise ASP.NET complains:

<%@ Page Language="C#" AutoEventWireup="true" EnableEventValidation="false" CodeBehind="Grid.aspx.cs" Inherits="CSharp_WebApp.Grid" %>