vb.net – DataGridView到CSV文件

我有一个VB 2010 Express项目,其中有一个DataGridView,我正在尝试写入CSV文件.

我写的都在工作.但它的速度很慢.慢速=可能30秒,超过8列6000行.

这是我的代码：

Private Sub btnExportData_Click(ByVal sender As System.Object,ByVal e As System.EventArgs) Handles btnExportData.Click
    Dim StrExport As String = ""
    For Each C As DataGridViewColumn In DataGridView1.Columns
        StrExport &= """" & C.HeaderText & ""","
    Next
    StrExport = StrExport.Substring(0,StrExport.Length - 1)
    StrExport &= Environment.NewLine

    For Each R As DataGridViewRow In DataGridView1.Rows
        For Each C As DataGridViewCell In R.Cells
            If Not C.Value Is Nothing Then
                StrExport &= """" & C.Value.ToString & ""","
            Else
                StrExport &= """" & "" & ""","
            End If
        Next
        StrExport = StrExport.Substring(0,StrExport.Length - 1)
        StrExport &= Environment.NewLine
    Next

    Dim tw As IO.TextWriter = New IO.StreamWriter("C:\Test1.CSV")
    tw.Write(StrExport)
    tw.Close()
End Sub

有谁知道我能做些什么来加快它？

谢谢

Dim headers = (From header As DataGridViewColumn In DataGridView1.Columns.Cast(Of DataGridViewColumn)() _
              Select header.HeaderText).ToArray
Dim rows = From row As DataGridViewRow In DataGridView1.Rows.Cast(Of DataGridViewRow)() _
           Where Not row.IsNewRow _
           Select Array.ConvertAll(row.Cells.Cast(Of DataGridViewCell).ToArray,Function(c) If(c.Value IsNot Nothing,c.Value.ToString,""))
Using sw As New IO.StreamWriter("csv.txt")
    sw.WriteLine(String.Join(",",headers))
    For Each r In rows
        sw.WriteLine(String.Join(",r))
    Next
End Using
Process.Start("csv.txt")