C＃中的GCHandle错误

Question

也许，有人可以帮助我。以下代码将C＃中的二维字符串数组传递给C ++，可以很好地处理GCHandle，它会产生错误：类型＆＃39; System.ArgumentException＆＃39;的未处理异常。发生在mscorlib.dll中 附加信息：对象不包含任何原始信息。 实际上，它与双2D完美配合。

public static extern void DDentry
(
[In][MarshalAs(UnmanagedType.LPArray, ArraySubType=UnmanagedType.BStr)] string[,] arrayReadDat, int iDim1, int iDim2
);

    private void button6_Click_1(object sender, EventArgs e)
    {
        Excel.Application appExcelREAD = new Excel.Application();
        appExcelREAD.Visible = true;

        string workbookPath = "C:\\Users\\Redstone\\Desktop\\eva_excel_input.xlsx";     // input file

        Excel.Workbook excelWorkbook1 = appExcelREAD.Workbooks.Open(workbookPath,
        0, false, 5, "", "", false, Microsoft.Office.Interop.Excel.XlPlatform.xlWindows, "",
        true, false, 0, true, false, false);

        Excel.Worksheet excelWorksheet1 = appExcelREAD.Worksheets["Tabelle1"];

        int lastRow = excelWorksheet1.UsedRange.Rows.Count;
        int lastCol = excelWorksheet1.UsedRange.Columns.Count;

        string[,] arrayReadDat = new string[lastRow+1, lastCol+1];

        for (int i = 2; i <= lastRow; i++)
        {
            for (int j = 1; j <= lastCol; j++)
            {
                arrayReadDat[i, j] = excelWorksheet1.Cells[i, j].Value2.ToString();
            }
        }

        excelWorkbook1.Close();
        appExcelREAD.Quit();

        GCHandle gch = GCHandle.Alloc(arrayReadDat, GCHandleType.Pinned);
        IntPtr pArrayData = gch.AddrOfPinnedObject();

        DDentry(arrayReadDat, lastRow+1, lastCol+1);

        gch.Free();