如何将两个或多个Excel数据或文件导入到Gridview

protected void btnUpload_Click(object sender, EventArgs e)
{
    if (fileUpload.HasFile)
    {
        // 保存上传的Excel文件到服务器上的临时位置
        string filePath = Server.MapPath("~/Temp/" + fileUpload.FileName);
        fileUpload.SaveAs(filePath);

        // 读取Excel文件的数据
        Microsoft.Office.Interop.Excel.Application excelApp = new Microsoft.Office.Interop.Excel.Application();
        Microsoft.Office.Interop.Excel.Workbook excelWorkbook = excelApp.Workbooks.Open(filePath);
        Microsoft.Office.Interop.Excel.Worksheet excelWorksheet = excelWorkbook.Sheets[1];
        Microsoft.Office.Interop.Excel.Range excelRange = excelWorksheet.UsedRange;

        // 将Excel数据转换为数据表
        DataTable dt = new DataTable();
        for (int i = 1; i <= excelRange.Columns.Count; i++)
        {
            dt.Columns.Add(excelRange.Cells[1, i].Value.ToString());
        }
        for (int row = 2; row <= excelRange.Rows.Count; row++)
        {
            DataRow dr = dt.NewRow();
            for (int col = 1; col <= excelRange.Columns.Count; col++)
            {
                dr[col - 1] = excelRange.Cells[row, col].Value.ToString();
            }
            dt.Rows.Add(dr);
        }

        // 绑定数据到GridView
        gridView.DataSource = dt;
        gridView.DataBind();

        // 关闭Excel对象
        excelWorkbook.Close();
        excelApp.Quit();
        System.Runtime.InteropServices.Marshal.ReleaseComObject(excelApp);
    }
}