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ASP.NET XML data binding

We can bind an XML file to the list control.

An XML file

There is a file named "countries.xml" XML file:

<?xml version="1.0" encoding="ISO-8859-1"?>

<countries>

<country>
<text>Norway</text>
<value>N</value>
</country>

<country>
<text>Sweden</text>
<value>S</value>
</country>

<country>
<text>France</text>
<value>F</value>
</country>

<country>
<text>Italy</text>
<value>I</value>
</country>

</countries>

Check the XML file: countries.xml

Bind DataSet to List Controls

First, import the "System.Data" namespace. We need this namespace to work with DataSet objects. The following instruction is included in the top of the .aspx page:

<%@ Import Namespace="System.Data" %>

Next, create a DataSet for the XML file, and when the page first loads this XML file loading DataSet:

<script runat="server">
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New DataSet
mycountries.ReadXml(MapPath("countries.xml"))
end if
end sub

To bind data to a RadioButtonList control, first create a RadioButtonList control in an .aspx page (without any asp: ListItem elements):

<html>
<body>

<form runat="server">
<asp:RadioButtonList id="rb" runat="server" AutoPostBack="True" />
</form>

</body>
</html>

Then add the script to create XML DataSet, and binds the value to the XML DataSet RadioButtonList control:

<%@ Import Namespace="System.Data" %>

<script runat="server">
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New DataSet
mycountries.ReadXml(MapPath("countries.xml"))
rb.DataSource=mycountries
rb.DataValueField="value"
rb.DataTextField="text"
rb.DataBind()
end if
end sub
</script>

<html>
<body>

<form runat="server">
<asp:RadioButtonList id="rb" runat="server"
AutoPostBack="True" onSelectedIndexChanged="displayMessage" />
</form>

</body>
</html>

Then we add a subroutine, when a user clicks on an item in the RadioButtonList control when the subroutine is executed. When a radio button is clicked, label will appear in the line of text:

Examples

<%@ Import Namespace="System.Data" %>

<script runat="server">
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New DataSet
mycountries.ReadXml(MapPath("countries.xml"))
rb.DataSource=mycountries
rb.DataValueField="value"
rb.DataTextField="text"
rb.DataBind()
end if
end sub

sub displayMessage(s as Object,e As EventArgs)
lbl1.text="Your favorite country is: " & rb.SelectedItem.Text
end sub
</script>

<html>
<body>

<form runat="server">
<asp:RadioButtonList id="rb" runat="server"
AutoPostBack="True" onSelectedIndexChanged="displayMessage" />
<p><asp:label id="lbl1" runat="server" /></p>
</form>

</body>
</html>

The demonstration >>