用GridView导入导出Excel,并打印GridView

1、Excel数据导入到数据库中：
在页面放置1个按钮控件(Button1)和1个文件上传控件(FileUpload1)
protected void Page_Load(object sender, EventArgs e)
{
GridView1.Visible = false;
}
protected void Button1_Click(object sender, EventArgs e)
{

try
{
if (FileUpload1.PostedFile.FileName != "")
{
string filepath = FileUpload1.PostedFile.FileName;
string filename = filepath.Substring(filepath.LastIndexOf("//") + 1);
string sheetname = "Sheet1";
string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + filepath + ";Extended Properties=Excel 8.0;";
OleDbConnection conn = new OleDbConnection(strConn);
OleDbDataAdapter oada = new OleDbDataAdapter("select * from [" + sheetname + "$]", conn);
DataSet ds = new DataSet();
oada.Fill(ds);
GridView1.DataSource = ds;
GridView1.DataBind();
GridView1.Visible = true;
}
}
catch (Exception error)
{
this.Label1.Text = "上传发生错误！原因：" + error.ToString();
}
}
注意把Excel文件属性中加入ASPNET用户权限，不然不能导入

3、将数据库中的数据导入Excel中，在这里我讲叙自己实践中的两个方法：

方法一：从最基本的写文件入手，将从数据库中读出来的数据写入到Excel中；

//该方法实现将数据导入到Excel文件中，其中的DataTable dt就是你需要将数据写入到Excel中的数据；
public void ExportExcel( DataTable dt , StreamWriter w )
...{
try
...{
for( int i = 0 ; i < dt.Columns.Count ; i ++ )
...{
w.Write ( dt.Columns[i] );
w.Write( ' ' );
}
w.Write ( " " );

object[] values = new object [dt.Columns.Count];
foreach ( DataRow dr in dt.Rows )
...{
values = dr.ItemArray ;
for ( int i = 0 ; i < dt.Columns.Count ; i++ )
...{
w.Write ( values[i] );
w.Write ( ' ' );
}
w.Write ( " " );
}
w.Flush();
w.Close();
}
catch
...{
w.Close();
}
}
StreamWriter w就是你自己创建的一个流，创建该数据流时，你需要自己指定需要将数据写入到那个文件，即指定文件路径，要实现下载的话，就可以简单的用Response.Redirect

( "指定需要被下载的文件路径" );

方法二：该方法实现的是将数据从DataGrid中导入到Excel中：

//filename为Excel的名字，ToExcelGrid就是数据源，在此为DataGrid数据源；
private void ExportExcelFromDataGrid( string filename , System.Web.UI.WebControls.DataGrid ToExcelGrid )
...{
Response.Clear();
Response.Buffer= true;
Response.Charset="utf-8";
Response.AppendHeader("Content-Disposition","attachment;filename="+Server.UrlEncode ( filename ) );
Response.ContentEncoding=System.Text.Encoding.GetEncoding("utf-8");//设置输出流为简体中文
Response.ContentType = "application/ms-excel";//设置输出文件类型为excel文件。
this.EnableViewState = false;
System.Globalization.CultureInfo myCItrad = new System.Globalization.CultureInfo("ZH-CN",true);
System.IO.StringWriter oStringWriter = new System.IO.StringWriter(myCItrad);
System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
ToExcelGrid.RenderControl(oHtmlTextWriter);
Response.Write(oStringWriter.ToString());
Response.End();

Excel导出：
页面上放一个GridView控件，ID为GridView1，添加个导出按钮ID为Button2

protected void Button2_Click(object sender, EventArgs e)
{
Response.Clear();
Response.Buffer = true;
Response.Charset = "GB2312";
Response.AppendHeader("Content-Disposition", "attachment;filename=FileName.xls");
// 如果设置为 GetEncoding("GB2312");导出的文件将会出现乱码！！！
Response.ContentEncoding = System.Text.Encoding.UTF7;
Response.ContentType = "application/ms-excel";//设置输出文件类型为excel文件。
System.IO.StringWriter oStringWriter = new System.IO.StringWriter();
System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
this.GridView1.RenderControl(oHtmlTextWriter);
Response.Output.Write(oStringWriter.ToString());
Response.Flush();
Response.End();

}

页面后台必须重写这两个方法，不然出现错误！
public override void VerifyRenderingInServerForm( Control control )
{

}
protected override void Render(HtmlTextWriter writer)
{
if (Page != null)
{
Page.VerifyRenderingInServerForm(this);
}
base.Render(writer);
}

将GridView打印出来，添加个打印按钮，ID为Button4
protected void Button4_Click(object sender, EventArgs e)
{
Response.Write("<script> window.print()</script>");
}