c#导出Excel

使用IO流，使用文件流在磁盘创建一个 Excel 文件，然后使用流写入数据

public static void ExportExcel(DataTable dt)
{
string path = AppDomain.CurrentDomain.BaseDirectory + "Export/";
if (!Directory.Exists(path))//验证路径是否存在
{
//不存在则创建
Directory.CreateDirectory(path);
}
//设置导出文件路径
//string path = HttpContext.Current.Server.MapPath("Export/");
//设置新建文件路径及名称
//string savePath = path + DateTime.Now.ToString("yyyy-MM-dd-HH-mm-ss") + ".xls";
string savePath = path + DateTime.Now.ToString("yyyy-MM-dd-HH-mm-ss") + ".xls";
if (File.Exists(savePath))
{
File.Delete(savePath);
}
//创建文件
FileStream file = new FileStream(savePath, FileMode.CreateNew, FileAccess.Write);
//以指定的字符编码向指定的流写入字符
StreamWriter sw = new StreamWriter(file, Encoding.GetEncoding("GB2312"));
StringBuilder strbu = new StringBuilder();
//写入标题
for (int i = 0; i < dt.Columns.Count; i++)
{
strbu.Append(dt.Columns[i].ColumnName.ToString() + " ");
}
//加入换行字符串
strbu.Append(Environment.NewLine);
//写入内容
for (int i = 0; i < dt.Rows.Count; i++)
{
for (int j = 0; j < dt.Columns.Count; j++)
{
strbu.Append(dt.Rows[i][j].ToString() + " ");
}
strbu.Append(Environment.NewLine);
}
sw.Write(strbu.ToString());
sw.Flush();
file.Flush();
sw.Close();
sw.Dispose();
file.Close();
file.Dispose();
}