how can i bind id to a button in gridview?

<asp:button id="Button1" 
            runat="server"
            CommandArgument='<%#Eval("id")%>' 
            CommandName="arun" 
            Text="View Details" />

protected void grd_question_RowCommand(object sender, GridViewCommandEventArgs e)
{
       if (e.CommandName == "arun";)
       {
           Int32 id = Convert.ToInt32(e.CommandArgument);

       }
}