2006年11月14日

把GridView控件的内容输出到Excel的方式网上有很多文章,其代码如下所示:

ExcelExport.aspx.cs 

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using System.Text;

using System.IO;

 

public partial class DeleteConfirm : System.Web.UI.Page

{

 

    protected void Page_Load(object sender, EventArgs e)

    {

    }

 

    protected void Button1_Click(object sender, EventArgs e)

    {

        //Export the GridView to Excel

        PrepareGridViewForExport(GridView1);

        ExportGridView();

    }

 

    private void ExportGridView()

    {

        string attachment = "attachment; filename=Contacts.xls";

        Response.ClearContent();

        Response.AddHeader("content-disposition", attachment);

        Response.ContentType = "application/ms-excel";

        StringWriter sw = new StringWriter();

        HtmlTextWriter htw = new HtmlTextWriter(sw);

        GridView1.RenderControl(htw);

        Response.Write(sw.ToString());

        Response.End();

    }

 

    public override void VerifyRenderingInServerForm(Control control)

    {

    }

 

    private void PrepareGridViewForExport(Control gv)

    {

        LinkButton lb = new LinkButton();

        Literal l = new Literal();

        string name = String.Empty;

        for (int i = 0; i < gv.Controls.Count; i++)

        {

            if (gv.Controls[i].GetType() == typeof(LinkButton))

            {

                l.Text = (gv.Controls[i] as LinkButton).Text;

                gv.Controls.Remove(gv.Controls[i]);

                gv.Controls.AddAt(i, l);

            }

            else if (gv.Controls[i].GetType() == typeof(DropDownList))

            {

                l.Text = (gv.Controls[i] as DropDownList).SelectedItem.Text;

                gv.Controls.Remove(gv.Controls[i]);

                gv.Controls.AddAt(i, l);

            }

            else if (gv.Controls[i].GetType() == typeof(CheckBox))

            {

                l.Text = (gv.Controls[i] as CheckBox).Checked ? "True" : "False";

                gv.Controls.Remove(gv.Controls[i]);

                gv.Controls.AddAt(i, l);

            }

            if (gv.Controls[i].HasControls())

            {

                PrepareGridViewForExport(gv.Controls[i]);

            }

        }

    }

}

通过对这段代码的测试,有两个地方应该注意,一个是重载VerifyRenderingInServerForm(Control control)方法,如果没有这个重载函数的话,GridView1.RenderControl(htw)这个语句会报一个“控件必须包含在runat=server的窗体内”错误,即使你的gridview已经包含在一个<form runat=server>的form中;另一个问题是必须在页面设置EnableEventValidation="false",否则会有一个"registerEventValidation必须在render中"的错误。