【下载文档:  使用CustomValidator自定义验证控件检查是否有对ListBox控件选择.txt 】

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使用CustomValidator自定义验证控件检查是否有对ListBox控件选择
在前网页前端处，我们放置ListBox控件，在数据提交前，检查用户是否有对此控件进行选择？ Insus.NET的方法是使用Javascript与CustomValidator自定义验证控件来检查。 可以看到最终结果： 你也想参此例子，可以参考下面数据与准备方法，写一个对象，它将用来产生十个天干。 HeavenlyStem.cs 复制代码 代码如下: using System; using System.Collections.Generic; using System.Linq; using System.Web; ///

/// Summary description for HeavenlyStem ///

public class HeavenlyStem { private int _ID; private string _Name; public int ID { get { return _ID; } set { _ID = value; } } public string Name { get { return _Name; } set { _Name = value; } } public HeavenlyStem() { // // TODO: Add constructor logic here // } public HeavenlyStem(int id, string name) { this.ID = id; this._Name = name; } } 产生与用泛型来存储它们： 复制代码 代码如下: private List GetHeavenStem() { List ListHS = new List(); HeavenlyStem hs = new HeavenlyStem(); hs.ID = 1; hs.Name = "甲"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 2; hs.Name = "乙"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 3; hs.Name = "丙"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 4; hs.Name = "丁"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 5; hs.Name = "戊"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 6; hs.Name = "己"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 7; hs.Name = "庚"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 8; hs.Name = "辛"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 9; hs.Name = "壬"; ListHS.Add(hs); hs = new HeavenlyStem(); hs.ID = 10; hs.Name = "癸"; ListHS.Add(hs); return ListHS; } Html标记： 复制代码 代码如下: 接下来，你需要在.aspx.cs为ListBox控件绑定数据，数据源即是刚才产生的List： 复制代码 代码如下: using System.Collections.Generic; using System.Data; using System.Data.OleDb; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using Insus.NET; public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) Data_Binding(); } private void Data_Binding() { this.ListBoxHeavenlyStem.DataSource = GetHeavenStem(); this.ListBoxHeavenlyStem.DataTextField = "Name"; this.ListBoxHeavenlyStem.DataValueField = "ID"; this.ListBoxHeavenlyStem.DataBind(); } } 最后是写Javascript脚本： 复制代码 代码如下: function ValidateListBox(sender, args) { var lb = document.getElementById("<%=ListBoxHeavenlyStem.ClientID%>") var options = lb.options; args.IsValid = false; for (var i = 0; i < options.length; i++) { if (options[i].selected == true) { args.IsValid = true; return; } } }