C# 操作excel 资料

using System;
using Excel=Microsoft.Office.Interop.Excel;
using System.Reflection;
using System.Data;
using System.Data.SqlClient;
using System.Windows.Forms;

namespace MailSend.classFile
{
    /**//// <summary>
    /// GetExcel の概要の説明です。
    /// </summary>
    public class GetExcel
    {
        private DataTable _table;
        private string _fileName;
        public GetExcel()
        {
            
        }
        public GetExcel(DataTable tb,string FileName)
        {
            _table=tb;
            _fileName=FileName;
        }        

        public void Down_Excel()
        {
            if(System.IO.File.Exists(_fileName))
            {
                System.IO.File.Delete(_fileName);
            }
                
            int rowCount=_table.Rows.Count;
            int coulumnCount=_table.Columns.Count;

            Excel.Application xl=new Excel.Application();
            Excel.Workbook xbook=xl.Application.Workbooks.Add(true);
            //xl.Application.Workbooks.Add(true);
            Excel.Worksheet excelWorkSheet = (Excel.Worksheet)xbook.Worksheets.Add(Missing.Value, Missing.Value, 1, Missing.Value);
            switch(classFile.Field.MailFlg)
            {
                case "1":
                    excelWorkSheet.Name = DateTime.Today.ToString("yyyyMMdd")+"ストコン⇔本社売上⇔現金管理";
                    break;
                case "2":
                    //excelWorkSheet.Name = DateTime.Today.ToString("yyyyMMdd")+"ストコン⇔本社売上⇔現金管理";
                    break;
                case "3":
                    excelWorkSheet.Name = DateTime.Today.ToString("yyyyMMdd")+"売上ヘッダー明細整合";
                    break;
                default:
                    //MessageBox.Show("起動バラメータがエラー。");
                    //Application.Exit();
                    break;
            }         
            

            int rowIndex = 2;
            int colIndex = 1;
            foreach(DataColumn col in _table.Columns)
            {
                colIndex++;
                Excel.Range cell=(Excel.Range)excelWorkSheet.Cells[2,colIndex];
                cell.Value2 = col.ColumnName;
                cell.Font.ColorIndex=5;  //3 red 5 blue 7 pink         
            }                
                    
//            foreach(DataRow row in _table.Rows)
//            {
//                rowIndex++;
//                colIndex = 1;
//                foreach(DataColumn col in _table.Columns)
//                {
//                    colIndex++;
//                    excelWorkSheet.Cells[rowIndex,colIndex]=row[col.ColumnName].ToString();
//                }
//            }            
             rowIndex = 0;
             colIndex = 0;            
            string [,] array=new string[rowCount,coulumnCount];
            try
            {
                foreach(DataRow row in _table.Rows)
                {
                
                    foreach(DataColumn col in _table.Columns)
                    {                        
                        array[rowIndex,colIndex]=row[col.ColumnName].ToString();
                        colIndex++;
                    }
                    rowIndex++;
                    colIndex = 0;
                }
            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.Message);
            }

            Excel.Range dataRange=excelWorkSheet.get_Range(excelWorkSheet.Cells[3,2],excelWorkSheet.Cells[rowCount+2,coulumnCount+1]);
            dataRange.Value2=array;

            
            
                
            Excel.Range select=excelWorkSheet.get_Range(excelWorkSheet.Cells[2,2],excelWorkSheet.Cells[2,coulumnCount+1]);
            select.Interior.ColorIndex=6;//backgroud
            select.EntireColumn.AutoFit();
            select.EntireRow.AutoFit();     
            select.HorizontalAlignment=Excel.XlHAlign.xlHAlignCenter;        
            select.VerticalAlignment = Excel.XlVAlign.xlVAlignCenter; //横
            select.Borders.LineStyle = BorderStyle.None;
            select.Borders.Weight = Excel.XlBorderWeight.xlThin;
            select.Borders.ColorIndex = Excel.XlColorIndex.xlColorIndexAutomatic;

            select=excelWorkSheet.get_Range(excelWorkSheet.Cells[3,2],excelWorkSheet.Cells[rowCount+2,4]);
            select.EntireColumn.AutoFit();
            select.EntireRow.AutoFit();     
            select.HorizontalAlignment=Excel.XlHAlign.xlHAlignLeft;
            select.VerticalAlignment = Excel.XlVAlign.xlVAlignCenter; 
            select.Borders.LineStyle = BorderStyle.None;
            select.Borders.Weight = Excel.XlBorderWeight.xlThin;
            select.Borders.ColorIndex = Excel.XlColorIndex.xlColorIndexAutomatic;

            select=excelWorkSheet.get_Range(excelWorkSheet.Cells[3,4],excelWorkSheet.Cells[rowCount+2,coulumnCount+1]);
            select.EntireColumn.AutoFit();
            select.EntireRow.AutoFit();     
            select.HorizontalAlignment=Excel.XlHAlign.xlHAlignRight;
            select.VerticalAlignment = Excel.XlVAlign.xlVAlignCenter; 
            select.Borders.LineStyle = BorderStyle.None;
            select.Borders.Weight = Excel.XlBorderWeight.xlThin;
//            select.Borders.ColorIndex = Excel.XlColorIndex.xlColorIndexAutomatic;                        
                
            xl.Visible = false;
            xbook.Saved = true;
            xl.DisplayAlerts=false;
            xbook.SaveCopyAs(_fileName);

            //xl.Visible = false;
            //                if(System.IO.File.Exists(FilePath))
            //                {
            //                    System.IO.File.Delete(FilePath);
            //                }
            //xl.DisplayAlerts=false;        

            //                Excel.Worksheet xSheet=(Excel.Worksheet)xbook.Sheets[1]; 
            //                xbook.SaveAs(FilePath,Missing.Value,Missing.Value,Missing.Value,Missing.Value,Missing.Value,Excel.XlSaveAsAccessMode.xlNoChange,Missing.Value,Missing.Value,Missing.Value,Missing.Value,Missing.Value); 
            //                
            //xl.ActiveWorkbook.SaveAs(FilePath,Excel.XlFileFormat.xlExcel9795,null,null,false,false,Excel.XlSaveAsAccessMode.xlNoChange,null,null,null,null,null);
                
            xl.Quit();                
            excelWorkSheet=null;
            xbook=null;
            xl=null;
            select=null;
            GC.Collect(); // ゴミ回収
            //}
        }
        

    }
}