exporting gridview to excel

[mrp9090]

I am using the following code to export my gridview to excel :

protected void btnExport_Click(object sender, ImageClickEventArgs e)
{
Response.Clear();
Response.AddHeader("content-disposition", "attachment;filename=FileName.xls");

Response.Charset = "";

// If you want the option to open the Excel file without saving than

// comment out the line below

// Response.Cache.SetCacheability(HttpCacheability.NoCache);

Response.ContentType = "application/vnd.ms-excel";

System.IO.StringWriter stringWrite = new System.IO.StringWriter();

System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);

GridView1.RenderControl(htmlWrite);

Response.Write(stringWrite.ToString());

Response.End();
}

public override void VerifyRenderingInServerForm(Control control)
{
// Confirms that an HtmlForm control is rendered for the specified ASP.NET server control at run time.
}

My problem is that I am setting the text values of one of the columns in the RowDataBound event, and doing so seems to mean that the text for this column is not exported, whereas if I don't set the text in the RowDataBound event, the text is exported.

Here is my code for RowDataBound:

switch (Probability.Text)
{
case "0.25":
e.Row.Cells[4].Text = "A (25%)";
e.Row.Cells[4].BackColor = System.Drawing.Color.PowderBlue;
break;

case "0.5":
e.Row.Cells[4].Text = "B (50%)";
e.Row.Cells[4].BackColor = System.Drawing.Color.DeepSkyBlue;
break;

Can anybody help with this?