Here is the class to export a gridview to an excel sheet:

Imports System
Imports System.Data
Imports System.Configuration
Imports System.IO
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls

Namespace ExcelExport
    Public NotInheritable Class GVExportUtil
        Private Sub New()
        End Sub

        Public Shared Sub Export(ByVal fileName As String, ByVal gv As GridView)
            HttpContext.Current.Response.Clear()
            HttpContext.Current.Response.AddHeader("content-disposition", String.Format("attachment; filename={0}", fileName))
            HttpContext.Current.Response.ContentType = "application/ms-excel"
            Dim sw As StringWriter = New StringWriter
            Dim htw As HtmlTextWriter = New HtmlTextWriter(sw)
            Dim table As Table = New Table
            table.GridLines = GridLines.Vertical
            If (Not (gv.HeaderRow) Is Nothing) Then
                GVExportUtil.PrepareControlForExport(gv.HeaderRow)
                table.Rows.Add(gv.HeaderRow)
            End If
            For Each row As GridViewRow In gv.Rows
                GVExportUtil.PrepareControlForExport(row)
                table.Rows.Add(row)
            Next
            If (Not (gv.FooterRow) Is Nothing) Then
                GVExportUtil.PrepareControlForExport(gv.FooterRow)
                table.Rows.Add(gv.FooterRow)
            End If
            table.RenderControl(htw)
            HttpContext.Current.Response.Write(sw.ToString)
            HttpContext.Current.Response.End()
        End Sub

        Private Shared Sub PrepareControlForExport(ByVal control As Control)
            Dim i As Integer = 0
            Do While (i < control.Controls.Count)
                Dim current As Control = control.Controls(i)
                If (TypeOf current Is LinkButton) Then
                    control.Controls.Remove(current)
                    control.Controls.AddAt(i, New LiteralControl(CType(current, LinkButton).Text))
                ElseIf (TypeOf current Is ImageButton) Then
                    control.Controls.Remove(current)
                    control.Controls.AddAt(i, New LiteralControl(CType(current, ImageButton).AlternateText))
                ElseIf (TypeOf current Is HyperLink) Then
                    control.Controls.Remove(current)
                    control.Controls.AddAt(i, New LiteralControl(CType(current, HyperLink).Text))
                ElseIf (TypeOf current Is DropDownList) Then
                    control.Controls.Remove(current)
                    control.Controls.AddAt(i, New LiteralControl(CType(current, DropDownList).SelectedItem.Text))
                ElseIf (TypeOf current Is CheckBox) Then
                    control.Controls.Remove(current)
                    control.Controls.AddAt(i, New LiteralControl(CType(current, CheckBox).Checked))
                End If
                If current.HasControls Then
                    GVExportUtil.PrepareControlForExport(current)
                End If
                i = (i + 1)
            Loop
        End Sub
    End Class

    End Namespace

Will this class cause memory leaks? And does anything here need to be disposed of? The code is working but I am getting the app pool falling over frequently when it is in use.

Thanks.