In this article I will explain with an example, how to get Cell value of GridView on Button Click in ASP.Net using C# and VB.Net.
The Button Click event will be implemented using the RowCommand event and hence when the Button is clicked, the RowCommand event will be triggered and inside it the cell value of the ASP.Net GridView will be fetched using C# and VB.Net.
HTML Markup
The following HTML Markup consists of an ASP.Net GridView with one BoundField column and two TemplateField columns, one containing a TextBox and the other containing a Button control whose CommandArgument property is bound to Container.DataItemIndex property.
Note: To learn more about Container.DataItemIndex property please refer my article Using Container.DataItemIndex property in ASP.Net GridView.
The OnRowCommand event handler has been set for the GridView.
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" OnRowCommand="GridView1_RowCommand">
        <asp:TemplateField HeaderText="Name" ItemStyle-Width="150">
                <asp:TextBox ID="txtName" runat="server" Text='<%# Eval("Name") %>' />
        <asp:BoundField DataField="Country" HeaderText="Country" ItemStyle-Width="150px" />
                <asp:Button Text="Select" runat="server" CommandName="Select" CommandArgument="<%# Container.DataItemIndex %>" />
You will need to import the following namespace.
using System.Data;
Imports System.Data
Binding the ASP.Net GridView control
I have created a dynamic DataTable with some dummy data and it is used to populate the GridView control in the Page Load event.
Note: You can learn more about this dynamic DataTable in my article Create DataTable dynamically and bind to GridView in ASP.Net.
protected void Page_Load(object sender, EventArgs e)
    if (!this.IsPostBack)
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[3] { new DataColumn("Id"), new DataColumn("Name"), new DataColumn("Country") });
        dt.Rows.Add(1, "John Hammond", "United States");
        dt.Rows.Add(2, "Mudassar Khan", "India");
        dt.Rows.Add(3, "Suzanne Mathews", "France");
        dt.Rows.Add(4, "Robert Schidner", "Russia");
        GridView1.DataSource = dt;
Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Dim dt As New DataTable()
        dt.Columns.AddRange(New DataColumn(2) {New DataColumn("Id"), New DataColumn("Name"), New DataColumn("Country")})
        dt.Rows.Add(1, "John Hammond", "United States")
        dt.Rows.Add(2, "Mudassar Khan", "India")
        dt.Rows.Add(3, "Suzanne Mathews", "France")
        dt.Rows.Add(4, "Robert Schidner", "Russia")
        GridView1.DataSource = dt
    End If
End Sub
Calling GridView RowCommand event on Button Click in ASP.Net
When the Select Button is clicked, the OnRowCommand event handler is executed. First the Button that was clicked is identified using the CommandName property of the GridViewCommandEventArgs object.
Then the row index is determined using the CommandArgument property of GridViewCommandEventArgs object and using the row index, the GridView Row is determined.
The TextBox control is referenced using the FindControl method of the GridView Row by passing the ID of the control as parameter. FindControl method returns the TextBox as an object of Control class and hence it has to be type casted to its respective type in order to access its properties.
The value of Name column is fetched from the TextBox, while the value of Country column is fetched from the GridView Cell based on the Column Index.
The name and country values are displayed using JavaScript Alert message box.
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
    if (e.CommandName == "Select")
        //Determine the RowIndex of the Row whose Button was clicked.
        int rowIndex = Convert.ToInt32(e.CommandArgument);
        //Reference the GridView Row.
        GridViewRow row = GridView1.Rows[rowIndex];
        //Fetch value of Name.
        string name = (row.FindControl("txtName") as TextBox).Text;
        //Fetch value of Country
        string country = row.Cells[1].Text;
        ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('Name: " + name + "\\nCountry: " + country + "');", true);
Protected Sub GridView1_RowCommand(sender As Object, e As GridViewCommandEventArgs)
    If e.CommandName = "Select" Then
        'Determine the RowIndex of the Row whose Button was clicked.
        Dim rowIndex As Integer = Convert.ToInt32(e.CommandArgument)
        'Reference the GridView Row.
        Dim row As GridViewRow = GridView1.Rows(rowIndex)
        'Fetch value of Name.
        Dim name As String = TryCast(row.FindControl("txtName"), TextBox).Text
        'Fetch value of Country.
        Dim country As String = row.Cells(1).Text
        ClientScript.RegisterStartupScript(Me.GetType(), "alert", "alert('Name: " & name & "\nCountry: " & country + "');", True)
    End If
End Sub
Get GridView Cell value on Button Click in ASP.Net using C# and VB.Net