/// <summary>
/// 将DataTable数据导出到EXCEL，调用该方法后自动返回可下载的文件流
/// </summary>
/// <param name="dtData">要导出的数据源</param>
public static void DataTable1Excel(System.Data.DataTable dtData)
{
System.Web.UI.WebControls.GridView gvExport = null;
// 当前对话
System.Web.HttpContext curContext = System.Web.HttpContext.Current;
// IO用于导出并返回excel文件
System.IO.StringWriter strWriter = null;
System.Web.UI.HtmlTextWriter htmlWriter = null;

if (dtData != null)
{
// 设置编码和附件格式
curContext.Response.ContentType = "application/vnd.ms-excel";
curContext.Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312");
curContext.Response.Charset = "utf-8";

// 导出excel文件
strWriter = new System.IO.StringWriter();
htmlWriter = new System.Web.UI.HtmlTextWriter(strWriter);
// 为了解决gvData中可能进行了分页的情况，需要重新定义一个无分页的GridView
gvExport = new System.Web.UI.WebControls.GridView();
gvExport.DataSource = dtData.DefaultView;
gvExport.AllowPaging = false;
gvExport.DataBind();

// 返回客户端
gvExport.RenderControl(htmlWriter);
curContext.Response.Write("<meta http-equiv=\"Content-Type\" content=\"text/html; charset=gb2312\" />" + strWriter.ToString());
curContext.Response.End();
}
}

/// <summary>
/// 直接输出Excel
/// </summary>
/// <param name="dtData"></param>
public static void DataTable2Excel(System.Data.DataTable dtData)
{
System.Web.UI.WebControls.DataGrid dgExport = null;
// 当前对话
System.Web.HttpContext curContext = System.Web.HttpContext.Current;
// IO用于导出并返回excel文件
System.IO.StringWriter strWriter = null;
System.Web.UI.HtmlTextWriter htmlWriter = null;

if (dtData != null)
{
// 设置编码和附件格式
curContext.Response.ContentType = "application/vnd.ms-excel";
curContext.Response.ContentEncoding = System.Text.Encoding.UTF8;
curContext.Response.Charset = "";

// 导出excel文件
strWriter = new System.IO.StringWriter();
htmlWriter = new System.Web.UI.HtmlTextWriter(strWriter);

// 为了解决dgData中可能进行了分页的情况，需要重新定义一个无分页的DataGrid
dgExport = new System.Web.UI.WebControls.DataGrid();
dgExport.DataSource = dtData.DefaultView;
dgExport.AllowPaging = false;
dgExport.DataBind();

// 返回客户端
dgExport.RenderControl(htmlWriter);
curContext.Response.Write(strWriter.ToString());
curContext.Response.End();
}
}

/// <summary>
/// dtData是要导出为Excel的DataTable,FileName是要导出的Excel文件名(不加.xls)
/// </summary>
/// <param name="dtData"></param>
/// <param name="FileName"></param>
private void MyDataTableExcel(System.Data.DataTable dtData, String FileName)
{
//当前对话
System.Web.HttpContext curContext = System.Web.HttpContext.Current;
//IO用于导出并返回excel文件
System.IO.StringWriter strWriter = null;
System.Web.UI.HtmlTextWriter htmlWriter = null;

if (dtData != null)
{
//设置编码和附件格式
//System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8)作用是方式中文文件名乱码
curContext.Response.AddHeader("content-disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8) + ".xls");
curContext.Response.ContentType = "application nd.ms-excel";
curContext.Response.ContentEncoding = System.Text.Encoding.UTF8;
curContext.Response.Charset = "GB2312";

//导出Excel文件
strWriter = new System.IO.StringWriter();
htmlWriter = new System.Web.UI.HtmlTextWriter(strWriter);

curContext.Response.Write(strWriter.ToString());
curContext.Response.End();
}
}

/// <summary>
/// dtData是要导出为Excel的DataTable,FileName是要导出的Excel文件名(不加.xls)
/// </summary>
/// <param name="dtData"></param>
/// <param name="FileName"></param>
private void DataTable3Excel(System.Data.DataTable dtData, String FileName)
{
System.Web.UI.WebControls.GridView dgExport = null;
//当前对话
System.Web.HttpContext curContext = System.Web.HttpContext.Current;
//IO用于导出并返回excel文件
System.IO.StringWriter strWriter = null;
System.Web.UI.HtmlTextWriter htmlWriter = null;

if (dtData != null)
{
//设置编码和附件格式
//System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8)作用是方式中文文件名乱码
curContext.Response.AddHeader("content-disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8) + ".xls");
curContext.Response.ContentType = "application nd.ms-excel";
curContext.Response.ContentEncoding = System.Text.Encoding.UTF8;
curContext.Response.Charset = "GB2312";

//导出Excel文件
strWriter = new System.IO.StringWriter();
htmlWriter = new System.Web.UI.HtmlTextWriter(strWriter);

//为了解决dgData中可能进行了分页的情况,需要重新定义一个无分页的GridView
dgExport = new System.Web.UI.WebControls.GridView();
dgExport.DataSource = dtData.DefaultView;
dgExport.AllowPaging = false;
dgExport.DataBind();

//下载到客户端
dgExport.RenderControl(htmlWriter);
curContext.Response.Write(strWriter.ToString());
curContext.Response.End();
}
}

/// <summary>
/// Datatable to Excel带自定文件名的导出
/// </summary>
/// <param name="dt"></param>
/// <param name="FileName"></param>
private void DataTable4Excel(System.Data.DataTable dt, string FileName)
{
System.IO.StringWriter stringWriter = new System.IO.StringWriter();
HtmlTextWriter htmlWriter = new HtmlTextWriter(stringWriter);
DataGrid excel = new DataGrid();
//System.Web.UI.WebControls.TableItemStyle AlternatingStyle = new TableItemStyle();
System.Web.UI.WebControls.TableItemStyle headerStyle = new TableItemStyle();
//System.Web.UI.WebControls.TableItemStyle itemStyle = new TableItemStyle();
//AlternatingStyle.BackColor = System.Drawing.Color.LightGray;
headerStyle.BackColor = System.Drawing.Color.LightGray;
headerStyle.Font.Bold = true;
headerStyle.HorizontalAlign = System.Web.UI.WebControls.HorizontalAlign.Center;
//itemStyle.HorizontalAlign = System.Web.UI.WebControls.HorizontalAlign.Center; ;

//excel.AlternatingItemStyle.MergeWith(AlternatingStyle);
excel.HeaderStyle.MergeWith(headerStyle);
//excel.ItemStyle.MergeWith(itemStyle);
excel.GridLines = GridLines.Both;
excel.HeaderStyle.Font.Bold = true;
excel.DataSource = dt.DefaultView; //输出DataTable的内容
excel.DataBind();

//for (int i = 0; i < excel.Items.Count; i++)
//{
// //excel.Columns[3].ItemStyle.CssClass = "xlsText";
// //excel.Items[i].Cells[3].Style.Add("mso-number-format", "\"@\"");
// for (int j = 0; j < aColTxtFormat.Length; j++)
// {
// int nCol = aColTxtFormat[j];
// excel.Items[i].Cells[nCol].Attributes.Add("style", "vnd.ms-excel.numberformat:@");
// }
//}
excel.RenderControl(htmlWriter);

HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=‘" + FileName + ".xls‘");
//HttpContext.Current.Response.Charset = "UTF-8";
HttpContext.Current.Response.Charset = "UTF-8";
HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("UTF-8");
//HttpContext.Current.Response.ContentType=".xls/.txt/.doc";image/JPEG;text/HTML;image/GIF;vnd.ms-excel/msword
HttpContext.Current.Response.ContentType = ".xls";
HttpContext.Current.Response.Write(stringWriter.ToString());
HttpContext.Current.Response.End();

}

导出excel