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asp.net - Change TreeView image set programmatically

Change TreeView image set programmatically
The TreeView is an asp.net web server control. The TreeView is located under System.Web.UI.WebControls namespace. TreeView web server control displays hierarchical data. Such as a table of contents in a tree structure.

The following asp.net c# tutorial code demonstrates how we can programmatically change the TreeView image set. The asp.net c# developers can change the image set of a TreeView programmatically using its ImageSet property.

The TreeView ImageSet property gets or sets the group of images to use for the TreeView control. The ImageSet property value is one of the TreeViewImageSet values. The default is TreeViewImageSet.Custom. In this asp.net tutorial, we set the TreeView ImageSet property value to TreeViewImageSet.Faq and TreeViewImageSet.Msdn on button click event.

The TreeViewImageSet.Faq is a predefined set of FAQ-styled images. And the TreeViewImageSet.Msdn is a predefined set of Microsoft MSDN developer program-styled images.

The TreeView ImageSet property throws ArgumentOutOfRangeException if the specified image set is not one of the TreeViewImageSet values.

The asp.net c# developers can use the ImageSet property to specify the group of images to use for the TreeView control. They can either select a predefined set of images to give the TreeView control a standard look or define their own custom set.
TreeViewImageSet.aspx

<%@ Page Language="C#" %>

<!DOCTYPE html>

<script runat="server">
    protected void Button1_Click(object sender, System.EventArgs e)
    {
        TreeView1.ImageSet = TreeViewImageSet.Faq;
    }
    protected void Button2_Click(object sender, System.EventArgs e)
    {
        TreeView1.ImageSet = TreeViewImageSet.Msdn;
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <title>How to set, change TreeView ImageSet (image set) programmatically</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h2 style="color:Red">TreeView Example: Change ImageSet</h2>
        <asp:SiteMapDataSource ID="SiteMapDataSource1" runat="server" />
        <asp:TreeView 
             ID="TreeView1"
             runat="server"
             DataSourceID="SiteMapDataSource1"
             Width="275"
             BorderWidth="2"
             BorderColor="SandyBrown"
             Font-Italic="true"
             >
        </asp:TreeView>
        <br />
        <asp:Button 
             ID="Button1" 
             runat="server"
             ForeColor="SeaGreen"
             Text="TreeView Faq ImageSet"
             Height="45"
             OnClick="Button1_Click"
             Font-Bold="true"
             />
        <asp:Button 
             ID="Button2" 
             runat="server"
             ForeColor="SeaGreen"
             Text="TreeView Msdn ImageSet"
             Height="45"
             OnClick="Button2_Click"
             Font-Bold="true"
             />
    </div>
    </form>
</body>
</html>
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