Question

I put some Image Buttons into my gridview, but I cannot capture the click event. Neither creating a click event, nor creating an OnRowCommand handler in the gridview works.

Clicking the buttons simply postbacks to the current page.

I add my buttons like this:

protected void gridview1_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        string status = DataBinder.Eval(e.Row.DataItem, "visitstatusuid").ToString();

        string visitUID = DataBinder.Eval(e.Row.DataItem, "visituid").ToString();

        Color backColor = Color.White;
        Color foreColor = Color.Black;

        ImageButton b;

        switch (status)
        {
            case "U": // Unallocated
                backColor = ColorTranslator.FromHtml("#B2A1C7");
                b = new ImageButton();
                b.Width = Unit.Pixel(25);
                b.Height = Unit.Pixel(30);
                b.AlternateText = "Book";
                b.ImageUrl = "../../Images/New/booking.gif";
                b.ToolTip = "Booking";
                b.CommandName = "Booking";
                b.CommandArgument = visitUID;
                b.CausesValidation = false;

                e.Row.Cells[(e.Row.Cells.Count - 3)].Controls.Add(b);

etc.

Answer 1

You’ll need to attach the handler when the button is created:

b.Click += MyButtonClickEventHandler;

Edit:
Instead of creating the button in the OnRowDataBound handler, use OnRowCreated.
This ensures the button is recreated on postbacks.

Example:

protected void Page_Load(object sender, EventArgs e)
{
  if (!IsPostBack) {
    BindData();
  }
}

protected void BindData()
{
  // Do your databinding here.
}

protected void MyGridView_RowCreated(object sender, GridViewRowEventArgs e)
{
  var b = new ImageButton();
  b.AlternateText = "Click Me!";
  // Etc.

  b.Click += MyButton_Click;
  // Add the button to the column you want.
}

protected void MyButton_Click(object sender, ImageClickEventArgs e)
{
  // Do your thing...
}