Repeated Value Binding : DataBinding Expressions « Data Binding « ASP.NET Tutorial






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<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="RepeatedValueBinding" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <table width="100%">
        <tr>
          <td>
            <select runat="server" ID="Select1" size="3" DataTextField="Key" DataValueField="Value"
              NAME="Select1" />
          </td>
          <td>
            <select runat="server" ID="Select2" DataTextField="Key" DataValueField="Value" NAME="Select2" />
          </td>
          <td>
            <asp:ListBox runat="server" ID="Listbox1" Size="3" DataTextField="Key" DataValueField="Value" />
          </td>
          <td>
            <asp:DropDownList runat="server" ID="DropdownList1" DataTextField="Key" DataValueField="Value" />
          </td>
          <td>
            <asp:RadioButtonList runat="server" ID="OptionList1" DataTextField="Key" DataValueField="Value" />
          </td>
          <td>
            <asp:CheckBoxList runat="server" ID="CheckList1" DataTextField="Key" DataValueField="Value" />
          </td>
        </tr>
      </table>
      <asp:Button runat="server" Text="Get Selection" ID="cmdGetSelection" OnClick="cmdGetSelection_Click" />
      <br>
      <br>
      <asp:Literal runat="server" ID="Result" EnableViewState="False" />
    </div>
    </form>
</body>
</html>

File: Default.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;

public partial class RepeatedValueBinding : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
    if (!Page.IsPostBack)
    {
      Hashtable ht = new Hashtable(3);
      ht.Add("value1", "Key1");
      ht.Add("value2", "Key2");
      ht.Add("value3", "Key3");

      Select1.DataSource = ht;
      Select2.DataSource = ht;
      Listbox1.DataSource = ht;
      DropdownList1.DataSource = ht;
      CheckList1.DataSource = ht;
      OptionList1.DataSource = ht;

      Page.DataBind();
    }
    }
  protected void cmdGetSelection_Click(object sender, EventArgs e)
  {
    if (Select1.SelectedIndex != -1)
      Result.Text += "- Item selected in Select1: " + Select1.Items[Select1.SelectedIndex].Text + " - " + Select1.Value + "<br>";
    
    if (Select2.SelectedIndex != -1)
      Result.Text += "- Item selected in Select2: " + Select2.Items[Select2.SelectedIndex].Text + " - " + Select2.Value + "<br>";

    if (Listbox1.SelectedIndex != -1)
      Result.Text += "- Item selected in Listbox1: " + Listbox1.SelectedItem.Text + " - " + Listbox1.SelectedItem.Value + "<br>";

    if (DropdownList1.SelectedIndex != -1)
      Result.Text += "- Item selected in DropdownList1: " + DropdownList1.SelectedItem.Text + " - " + DropdownList1.SelectedItem.Value + "<br>";

    if (OptionList1.SelectedIndex != -1)
      Result.Text += "- Item selected in OptionList1: " + OptionList1.SelectedItem.Text + " - " + OptionList1.SelectedItem.Value + "<br>";

    if (CheckList1.SelectedIndex != -1)
    {
      Result.Text += "- Items selected in CheckList1: ";
      foreach (ListItem li in CheckList1.Items)
      {
        if (li.Selected)
          Result.Text += li.Text + " - " + li.Value + " ";
      }
    }
  }
}








19.7.DataBinding Expressions
19.7.1.Understanding Templates and DataBinding Expressions
19.7.2.A template can contain other controls
19.7.3.Call other methods than the Eval() method in a DataBinding expression
19.7.4.Single value binding
19.7.5.Repeated Value Binding