C# DataGridView导出Excel的两种经典方法

第一种是用数据流导出:

#region
SaveFileDialog saveFileDialog = new SaveFileDialog();
saveFileDialog.Filter = "Execl files (*.xls)|*.xls";
saveFileDialog.FilterIndex = 0;
saveFileDialog.RestoreDirectory = true;
saveFileDialog.CreatePrompt = true;
saveFileDialog.Title = "Export Excel File";
saveFileDialog.ShowDialog();
if (saveFileDialog.FileName == "")
return;
Stream myStream;
myStream = saveFileDialog.OpenFile();
StreamWriter sw = new StreamWriter(myStream, System.Text.Encoding.GetEncoding(-0));

string str = "";
try
{
for (int i = 0; i < dataGridView1.ColumnCount; i++)
{
if (i > 0)
{
str += "\t";
}
str += dataGridView1.Columns[i].HeaderText;
}
sw.WriteLine(str);
for (int j = 0; j < dataGridView1.Rows.Count; j++)
{
string tempStr = "";
for (int k = 0; k < dataGridView1.Columns.Count; k++)
{
if (k > 0)
{
tempStr += "\t";
}
tempStr += dataGridView1.Rows[j].Cells[k].Value.ToString();
}
sw.WriteLine(tempStr);
}
sw.Close();
myStream.Close();
}

catch (Exception ex)
{
//MessageBox.Show(ex.ToString());
}
finally
{
sw.Close();
myStream.Close();
}
#endregion

这种方法的优点就是导出比较快，但是excel的表格里面设置标题，字体样式等都不能弄，因为你是用数据流直接导出为excel的，除非你能在数据流中设置这些样式，这个我还没这本事，哪位大哥会的教一下...嘿嘿

第二种方法是直接写一个类，这个类直接操作EXCEL的：

using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Text;
using System.Diagnostics;
using System.IO;
using Microsoft.Office.Interop.Excel;

namespace Excel
{
public class Export
{
/// <summary>
/// DataGridView导出Excel
/// </summary>
/// <param name="strCaption">Excel文件中的标题</param>
/// <param name="myDGV">DataGridView 控件</param>
/// <returns>0:成功;1:DataGridView中无记录;2:Excel无法启动;9999:异常错误</returns>
public int ExportExcel(string strCaption, DataGridView myDGV, SaveFileDialog saveFileDialog)
{
int result = 9999;

//保存

saveFileDialog.Filter = "Execl files (*.xls)|*.xls";
saveFileDialog.FilterIndex = 0;
saveFileDialog.RestoreDirectory = true;
//saveFileDialog.CreatePrompt = true;
saveFileDialog.Title = "Export Excel File";
if ( saveFileDialog.ShowDialog()== DialogResult.OK)
{
if (saveFileDialog.FileName == "")
{
MessageBox.Show("请输入保存文件名！");
saveFileDialog.ShowDialog();
}
// 列索引，行索引，总列数，总行数
int ColIndex = 0;
int RowIndex = 0;
int ColCount = myDGV.ColumnCount;
int RowCount = myDGV.RowCount;

if (myDGV.RowCount == 0)
{
result = 1;
}

// 创建Excel对象
Microsoft.Office.Interop.Excel.Application xlApp = new Microsoft.Office.Interop.Excel.ApplicationClass();
if (xlApp == null)
{
result = 2;
}
try
{
// 创建Excel工作薄
Microsoft.Office.Interop.Excel.Workbook xlBook = xlApp.Workbooks.Add(true);
Microsoft.Office.Interop.Excel.Worksheet xlSheet = (Microsoft.Office.Interop.Excel.Worksheet)xlBook.Worksheets[1];
// 设置标题
Microsoft.Office.Interop.Excel.Range range = xlSheet.get_Range(xlApp.Cells[1, 1], xlApp.Cells[1, ColCount]); //标题所占的单元格数与DataGridView中的列数相同
range.MergeCells = true;
xlApp.ActiveCell.FormulaR1C1 = strCaption;
xlApp.ActiveCell.Font.Size = 20;
xlApp.ActiveCell.Font.Bold = true;
xlApp.ActiveCell.HorizontalAlignment = Microsoft.Office.Interop.Excel.Constants.xlCenter;
// 创建缓存数据
object[,] objData = new object[RowCount + 1, ColCount];
//获取列标题
foreach (DataGridViewColumn col in myDGV.Columns)
{
objData[RowIndex, ColIndex++] = col.HeaderText;
}
// 获取数据
for (RowIndex = 1; RowIndex < RowCount; RowIndex++)
{
for (ColIndex = 0; ColIndex < ColCount; ColIndex++)
{
if (myDGV[ColIndex, RowIndex - 1].ValueType == typeof(string)
|| myDGV[ColIndex, RowIndex - 1].ValueType == typeof(DateTime))//这里就是验证DataGridView单元格中的类型,如果是string或是DataTime类型,则在放入缓存时在该内容前加入" ";
{
objData[RowIndex, ColIndex] = "" + myDGV[ColIndex, RowIndex - 1].Value;
}
else
{
objData[RowIndex, ColIndex] = myDGV[ColIndex, RowIndex - 1].Value;
}
}
System.Windows.Forms.Application.DoEvents();
}
// 写入Excel
range = xlSheet.get_Range(xlApp.Cells[2, 1], xlApp.Cells[RowCount, ColCount]);
range.Value2 = objData;

xlBook.Saved = true;
xlBook.SaveCopyAs(saveFileDialog.FileName);
}
catch (Exception err)
{
result = 9999;
}
finally
{
xlApp.Quit();
GC.Collect(); //强制回收
}
//返回值
result = 0;
}

return result;
}

}
}

这个优点是能设置样式什么的。缺点就是导出速度慢...

以上两种方法都是参考了很多料的..写在这里以便于相互学习..

补充一下：用第二种方法导出excel会有格式方面的变化，比如身份证号码按科学计算法导出了，不是按原先的模型

改进方法是在写入excel时添加一个格式声明：range.NumberFormatLocal = "@";

如：// 写入Excel

range = xlSheet.get_Range(xlApp.Cells[2, 1], xlApp.Cells[RowCount + 2, ColCount]);
range.NumberFormatLocal = "@";
range.Value2 = objData;