asp.net的com方式导出excel

最近做个项目，需要导出excel，要主从表一起导出的，就大致写了一个方法，可能格式方面还是会进行修改，先贴出来方便以后查看
项目引用微软excel的com的dll即可
/// <summary>
/// 功能：导出文件（通过数据源导出,可主从表导出）
/// </summary>
/// <param name="strTitle">文件名字</param>
/// <param name="mainDT">主表数据源</param>
/// <param name="dtParams">从表数据源集合</param>
public static void Export(string strTitle, System.Data.DataTable mainDT, params System.Data.DataTable[] dtParams)
{
GC.Collect();
Application oApp = new Application();
Workbooks oBooks = oApp.Workbooks;
Workbook oBook = oBooks.Add(true);
Worksheet oSheet = (Worksheet)oBook.ActiveSheet;
int _rowIndex = 4;//行索引
int _cellIndex = 1;//列索引
int _maxCellIndex = 1;//最大列索引
int _mainRowIndex = 4;//主表行索引
//绘制标题
oSheet.Cells[2, 2] = strTitle;
//绘制主表数据
foreach (DataColumn col in mainDT.Columns)
{
_cellIndex++;
//设置一行两列
if (_cellIndex > 17)
{
_rowIndex++;
_cellIndex = 2;
}
oSheet.Cells[_rowIndex, _cellIndex] = col.ColumnName+":";
oSheet.get_Range(oSheet.Cells[_rowIndex, _cellIndex], oSheet.Cells[_rowIndex, _cellIndex + 2]).Select();
oSheet.get_Range(oSheet.Cells[_rowIndex, _cellIndex], oSheet.Cells[_rowIndex, _cellIndex + 2]).HorizontalAlignment = XlHAlign.xlHAlignCenterAcrossSelection;
_cellIndex = _cellIndex + 3;
if (col.DataType == System.Type.GetType("System.DateTime"))// 日期格式
{
oSheet.Cells[_rowIndex, _cellIndex] =Convert.ToDateTime(mainDT.R