如何将旧 Excel 文件中多张工作表中的数据导出到新 Excel 文件中的一张工作表中

我试图导出包含多张工作表的 excel 文件，并且每张工作表都有一个数据（可能是 50-70 行）。

好吧，在旧的 Excel 文件中，它包含大约 169 个工作表，因此当您将 169 和 50 相乘时，新 Excel 文件中将包含 8450 行

但是当我尝试执行代码时，结果将只包含 500 行。这是我正在尝试的代码

private void button2_Click(object sender, EventArgs e)
{
FileInfo fileInfo = new FileInfo("C:\\Documents\\testFile.xlsm"); 
            string full = fileInfo.DirectoryName + "\\testResult.xlsx"; //Location for new Excel file that contain the result

            xlApp = new Excel.Application();
            xlWb = xlApp.Workbooks.Open("C:\\Documents\\testFile.xlsm");//Open the file
            xlWS = xlWb.Sheets[xlWb.Sheets.Count];//Count the sheets
            xlApp1 = new Excel.Application();
            xlWb1 = xlApp1.Workbooks.Add();
            int roww;//variable to save last number of row in the new excel file


            for (int i = 2; i <xlWb.Sheets.Count; i++) // looping
            {
                xlWb.Sheets[i].Activate();
                xlRange = xlWS.UsedRange;
                row = xlRange.Rows.Count;
                col = xlRange.Columns.Count;


                xlWS1 = (Excel.Worksheet)xlWb1.Worksheets.get_Item(1);
                xlRange1 = xlWS1.UsedRange;
                roww = xlRange1.Rows.Count;
                fulldata = new string[row][];
                //for transfer data to temp variable
                for (int j = 0; j < fulldata.Length; j++)
                {
                    fulldata[j] = new string[col];

                }
                for(int k = 0 ; k<row;k++)
                {
                    for (int l = 0; l < col; l++)
                    {
                        fulldata[k][l] = xlWS.Cells[k + 1, l + 1].value2.ToString();
                    }
                }
                //too export the data
                if (roww == 1) //if to count how many roww there is in the new file, if there is no data then it just put the data from the first row
                {
                    for (int k = 0; k <row; k++)
                    {
                        for (int l = 0; l < col; l++)
                        {
                            xlWS1.Cells[k + 1, l + 1] = fulldata[k][l];
                        }
                    }
                }
                else // if the file contain data from last sheet *means there will be more than 1 rows already fiiled
                {
                    for (int k = 0; k < row; k++)
                    {
                        for (int l = 0; l < col; l++)
                        {
                            xlWS1.Cells[roww + 1, l + 1] = fulldata[k][l];
                        }
                    }
                }
            }
            xlWb.Save();
            xlWb.Close();
            xlWb1.SaveAs(full, Excel.XlFileFormat.xlOpenXMLWorkbook, missing, missing,
            false, false, Excel.XlSaveAsAccessMode.xlNoChange, missing, missing, missing, missing, missing);
            xlWb1.Close();
            closeExcel(xlApp);
            closeExcel(xlApp1);
}

预期的结果是结果将有 8450 行，其中包含我要导出的多个工作表中的数据

实际结果只有 500 行，也许有人可以纠正我的代码，我不知道我在这里错过了什么