C#将DataTable数据导出CSV文件

C#将DataTable数据导出CSV文件通用方法！

//导出按钮调用导出方法
    protected void btnCSV_Click(object sender, EventArgs e)
    {
        DataTable dt = ExportData();//获取datatable数据源
        string title = "RPT_RC_BILLING_2020_LEOPARD_" + DateTime.Now.ToString("yyyyMMddHHmmss") + ".CSV";//导出的文件名
        EstablishCSV(dt,title);//将dt数据源和文件名title代入导出方法中
    }

/// 将DataTable中数据写入到CSV文件中
    /// </summary>
    /// <param name="dt">提供保存数据的DataTable</param>
    /// <param name="fileName">CSV的文件名</param>
    private void EstablishCSV(DataTable dt,string fileName)
    {
        HttpContext.Current.Response.Clear();
        System.IO.StringWriter sw = new System.IO.StringWriter();
        int iColCount = dt.Columns.Count;
        for (int i = 0; i < iColCount; i++)//表头
        {
            sw.Write(""" + dt.Columns[i] + """);
            if (i < iColCount - 1)
            {
                sw.Write(",");
            }
        }
        sw.Write(sw.NewLine);
        foreach (DataRow dr in dt.Rows)//行内数据
        {
            for (int i = 0; i < iColCount; i++)
            {
                if (!Convert.IsDBNull(dr[i]))
                    sw.Write(""" + dr[i].ToString() + """);
                else
                    sw.Write("""");
                if (i < iColCount - 1)
                {
                    sw.Write(",");
                }
            }
            sw.Write(sw.NewLine);
        }
        sw.Close();
        HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename="+ fileName);
        HttpContext.Current.Response.ContentType = "application/vnd.ms-excel";
        HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
        HttpContext.Current.Response.Write(sw);
        HttpContext.Current.Response.End();
    }