20230509001 - DataTable 导出成Excel

            DataTable dt_e = DataSet0.Tables[0];

            SaveFileDialog saveFileDialog = new SaveFileDialog();
            saveFileDialog.Filter = "Execl files (*.xls)|*.xls";
            saveFileDialog.FilterIndex = 0;
            saveFileDialog.RestoreDirectory = true;
            saveFileDialog.CreatePrompt = true;
            saveFileDialog.Title = "保存为Excel文件";
            if (saveFileDialog.ShowDialog() == DialogResult.OK)
            {
                Stream stream = saveFileDialog.OpenFile();
                StreamWriter sw = new StreamWriter(stream, System.Text.Encoding.GetEncoding(-0));

                string columnTitle = "";
                try
                {
                    for (int i = 0; i < dt_e.Rows.Count; i++)
                    {
                        if (i > 0)
                        {
                            columnTitle += "\t";//或者为逗号
                        }
                        //columnTitle += dt_e.Columns[i].HeaderText;//写入列标题
                        columnTitle += dt_e.Columns[i].Caption.ToString();//写入列标题
                    }
                    sw.WriteLine(columnTitle);
                    for (int j = 0; j < dt_e.Rows.Count; j++)
                    {
                        string columnValue = "";
                        for (int k = 0; k < dt_e.Columns.Count; k++)
                        {
                            if (k > 0)
                            {
                                columnValue += "\t";
                            }
                            //columnValue += dt_e.Rows[j].Cells[k].Value.ToString();
                            columnValue += dt_e.Rows[j][k].ToString();
                        }
                        sw.WriteLine(columnValue);
                    }
                    sw.Close();
                    stream.Close();
                }
                finally
                {
                    sw.Close();
                    stream.Close();
                }
            }