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[Solved] ToExcelML throwing Specified cast is not valid.

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GridView

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Fransiscus Setiawan asked on 25 May 2010, 03:51 AM

Hi,

I've got a problem with ToExcelML() extension method for RadGridView, I tried the other method of ToCSV which is working fine.

Code Behind

    
               Dim dialog As New SaveFileDialog() With {.Filter = "EXCEL files (*.xls)|*.xls|All files (*.*)|*.*"} 
        
                    If dialog.ShowDialog() = True Then 
        
                        Using stream As Stream = dialog.OpenFile() 
        
                            Using writer As New StreamWriter(stream, Encoding.UTF8) 
        
                                writer.Write(dgResults.ToExcelML()) 
        
                            End Using 
        
                            stream.Close() 
        
                        End Using 
        
                    End If

    
                Private Sub ExportResults_Exporting(ByVal sender As Object, ByVal e As Telerik.Windows.Controls.GridViewExportEventArgs) Handles dgResults.Exporting 
        
                    'Change the font size and the background color of the table header only 
        
                    If (e.Element = ExportElement.HeaderRow Or e.Element = ExportElement.HeaderCell) Then 
        
                        e.FontSize = e.FontSize + 4 
        
                        e.Background = Colors.DarkGray 
        
                        'Change the font size and the background color of the group headers only 
        
                    ElseIf (e.Element = ExportElement.GroupHeaderCell Or e.Element = ExportElement.GroupHeaderRow) Then 
        
                        e.FontSize = e.FontSize + 2 
        
                        e.Background = Colors.LightGray 
        
                    End If 
        
                End Sub

XAML

    
                  <telerikGrid:RadGridView x:Name="dgResults" Canvas.Left="-1500" Grid.Row="1"  
        
                            Grid.Column="0" AutoGenerateColumns="False" Exporting="ExportResults_Exporting" CanUserFreezeColumns="False"></telerikGrid:RadGridView>

The column definition is being generated on the fly inside the async_completed of WCF.

The error that I'm getting is "Specified cast is not valid".

3 Answers, 1 is accepted

Accepted