ASP.NET Web Forms - XML Files
We can bind an XML file to a list control.
An XML File
Here is an XML file named "countries.xml":
<?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>
Take a look at the XML file: countries.xml
Bind a DataSet to a List Control
First, import the "System.Data" namespace. We need this namespace to work with DataSet objects. Include the following directive at the top of an .aspx page:
<%@ Import Namespace="System.Data" %>
Next, create a DataSet for the XML file and load the XML file into the DataSet when the page is first loaded:
<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 the DataSet to a RadioButtonList control, first create a RadioButtonList control (without any asp:ListItem elements) in an .aspx page:
<html>
<body>
<form runat="server">
<asp:RadioButtonList id="rb" runat="server"
AutoPostBack="True" />
</form>
</body>
</html>
Then add the script that builds the XML DataSet:
<%@ 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 sub routine to be executed when the user clicks on an item in the RadioButtonList control. When a radio button is clicked, a text will appear in a label:
Example
<%@ 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>
Show example »