本文介紹如何在ASP.NET中實現多頁面選擇的問題。其具體思路很簡單:用隱藏的INPUT記住每次選擇的項目,在進行資料繫結時,檢查儲存的值,再在DataGrid中進行選中顯示。下面時完整的代碼和例子:
查看例子
SelectMultiPages.aspx
<%@ Page EnableViewState="true" CodeBehind="SelectMultiPages.aspx.cs" Language="c#"
AutoEventWireup="false" Inherits="eMeng.Exam.SelectMultiPages" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<title>跨頁面實現多選</title>
<META http-equiv="content-type" content="text/html; charset=gb2312">
<style>
* {FONT-SIZE:12PX}
#Status {text-align:left}
</style>
<script language="JAVASCRIPT">
function AddRemoveValues(oChk) {
//在處理這個地方需要注意的是:你儲存的值應該具有唯一性,這樣才能不會替換錯誤的項。
if(oChk.checked)
SelectMultiPage.HdnSelectedValues.value += "," + oChk.value;
else
SelectMultiPage.HdnSelectedValues.value = SelectMultiPage.HdnSelectedValues.value.replace("," + oChk.value,"");
}
</script>
</HEAD>
<BODY>
<form id="SelectMultiPage" runat="server">
<asp:datagrid id="DataGrid1" HorizontalAlign="Center" AutoGenerateColumns="False" Width="600px"
AllowPaging="True" runat="server">
<AlternatingItemStyle BackColor="#EEEEEE"></AlternatingItemStyle>
<HeaderStyle BackColor="#AAAADD" Font-Bold="True" HorizontalAlign="Center"></HeaderStyle>
<PagerStyle HorizontalAlign="Right" Mode="NumericPages" Visible="True"></PagerStyle>
<Columns>
<asp:TemplateColumn HeaderText="選擇">
<ItemTemplate>
<input type="checkbox" runat="server" id="chkSelect" onclick="AddRemoveValues(this)"
value='<%#DataBinder.Eval(Container.DataItem,"Title")%>'/>
</ItemTemplate>
</asp:TemplateColumn>
<asp:TemplateColumn HeaderText="文章標題">
<ItemTemplate>
<asp:Literal Text='<%# DataBinder.Eval(Container.DataItem, "Title") %>' runat="server" ID="TitleShow"/>
</ItemTemplate>
</asp:TemplateColumn>
<asp:TemplateColumn HeaderText="發布時間">
<ItemTemplate>
<asp:Literal Text='<%# DataBinder.Eval(Container.DataItem, "CreateDate").ToString() %>' runat="server"/>
</ItemTemplate>
</asp:TemplateColumn>
</Columns>
</asp:datagrid>
<div align=center>
<asp:button id="Button1" runat="server" Text="得到所選的值"></asp:button>
<div id="Status">
<asp:label id="Label1" runat="server"></asp:label>
</div>
<INPUT id="HdnSelectedValues" type="hidden" name="HdnSelectedValues" runat="server">
</div>
</form>
</BODY>
</HTML>
SelectMultiPages.aspx.cs
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Data.OleDb;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
namespace eMeng.Exam
{
/// <summary>
/// SelectMultiPages 的摘要說明。
/// </summary>
public class SelectMultiPages : System.Web.UI.Page
{
protected System.Web.UI.WebControls.Button Button1;
protected System.Web.UI.WebControls.Label Label1;
protected System.Web.UI.HtmlControls.HtmlInputHidden HdnSelectedValues;
protected System.Web.UI.WebControls.DataGrid DataGrid1;
private void Page_Load(object sender, System.EventArgs e)
{
// 在此處放置使用者代碼以初始化頁面
if(!Page.IsPostBack)
BindData();
}
private void DataGrid1_PageIndexChanged(object source, DataGridPageChangedEventArgs e)
{
DataGrid1.CurrentPageIndex = e.NewPageIndex;
BindData();
}
void BindData()
{
OleDbConnection cn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source="
+ HttpContext.Current.Server.MapPath("aspx.mdb"));
OleDbDataAdapter da = new OleDbDataAdapter("Select Title, CreateDate from Document",cn);
DataSet ds = new DataSet();
da.Fill(ds);
DataGrid1.DataSource= ds;
DataGrid1.DataBind();
}
private void DataGrid1_ItemDataBound(object sender, System.Web.UI.WebControls.DataGridItemEventArgs e)
{
//重新顯示所選擇的項目
if(e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{
if(HdnSelectedValues.Value.IndexOf(((Literal)e.Item.Cells[1].FindControl("TitleShow")).Text) >= 0 )
{
HtmlInputCheckBox ChkSelected = (HtmlInputCheckBox)(e.Item.Cells[0].FindControl("ChkSelect"));
ChkSelected.Checked = true;
}
}
}
private void Button1_Click(object sender, System.EventArgs e)
{
//為了顯示的方便進行替換的
Label1.Text = HdnSelectedValues.Value.Replace(",","<li>");
}
#region Web Form設計器產生的程式碼
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: 該調用是 ASP.NET Web Form設計器所必需的。
//
InitializeComponent();
base.OnInit(e);
}
/// <summary>
/// 設計器支援所需的方法 - 不要使用代碼編輯器修改
/// 此方法的內容。
/// </summary>
private void InitializeComponent()
{
this.DataGrid1.ItemDataBound +=
new System.Web.UI.WebControls.DataGridItemEventHandler(this.DataGrid1_ItemDataBound);
this.DataGrid1.PageIndexChanged +=
new System.Web.UI.WebControls.DataGridPageChangedEventHandler(this.DataGrid1_PageIndexChanged);
this.Button1.Click += new System.EventHandler(this.Button1_Click);
this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
}
}