EXCEl 导出

        /// <summary> 
        /// 将指定的Dataset导出到Excel文件 
        /// </summary> 
        /// <param name="dt"></param> 
        /// <returns></returns> 

                        DataTable dt = (DataTable)fmt.GetFormatData_(re);
                        string[] str = new string[2];
                        str[0] = "权限名称";
                        str[1] = "用户";
                        DataSet ds = new DataSet();
                        ds.Tables.Add(dt.Copy());
                        QXJS.qXJS.ExportToExcel(ds, "权限用户", str);


        public bool ExportToExcel(DataSet ds, string ReportName, string[] columnName)
        {
            if (ds.Tables[0].Rows.Count == 0)
            {
                MessageBox.Show("数据集为空");
            }
            Microsoft.Office.Interop.Excel._Application xlapp = new Microsoft.Office.Interop.Excel.ApplicationClass();
            try
            {
                Microsoft.Office.Interop.Excel.Workbook xlbook = xlapp.Workbooks.Add(true);
                Microsoft.Office.Interop.Excel.Worksheet xlsheet = (Microsoft.Office.Interop.Excel.Worksheet)xlbook.Worksheets[1];
                Microsoft.Office.Interop.Excel.Range range = xlsheet.get_Range(xlapp.Cells[1, 1], xlapp.Cells[1, ds.Tables[0].Columns.Count]);
                range.MergeCells = true;
                xlapp.ActiveCell.FormulaR1C1 = ReportName;
                xlapp.ActiveCell.Font.Size = 20;
                xlapp.ActiveCell.Font.Bold = true;
                xlapp.ActiveCell.HorizontalAlignment = Microsoft.Office.Interop.Excel.Constants.xlCenter;
                xlapp.Visible = true;
                int colIndex = 0;
                int RowIndex = 2;
                //开始写入每列的标题 
                foreach (string dc in columnName)
                {
                    colIndex++;
                    xlsheet.Cells[RowIndex, colIndex] = dc;
                }
                //开始写入内容 
                string flag = null;
                int RowCount = ds.Tables[0].Rows.Count;//行数 
                for (int i = 0; i < RowCount; i++)
                {
                    RowIndex++;
                    int ColCount = ds.Tables[0].Columns.Count;//列数 

 

                    for (colIndex = 1; colIndex <= ColCount; colIndex++)
                    {
                        if (i == 0 && colIndex == 1)
                        {
                            flag = ds.Tables[0].Rows[i][colIndex - 1].ToString();
                        }
                        if (colIndex == 1)
                        {
                            string value = ds.Tables[0].Rows[i][colIndex - 1].ToString();
                            if (flag != value)
                            {
                                RowIndex++;
                                xlsheet.Cells[RowIndex, 1] = ds.Tables[0].Rows[i][1 - 1].ToString();
                                xlsheet.Cells[RowIndex, 2] = ds.Tables[0].Rows[i][2 - 1].ToString();
                                flag = value;
                                break;
                            }
                            else
                            {
                                xlsheet.Cells[RowIndex, colIndex] = value;
                            }
                        }
                        else
                        {
                            xlsheet.Cells[RowIndex, colIndex] = ds.Tables[0].Rows[i][colIndex - 1].ToString();
                        }
                    }

                }
              
                xlbook.Saved = true;
                xlbook.SaveCopyAs(filePath+".xls");
                xlapp.Quit();
                GC.Collect();
                MessageBox.Show("导出完成");
                return true;
            }
            catch (Exception e1)
            {
                MessageBox.Show(e1.Message + "/ExportToExcel/导出excel");
                return false;
            }
        }