Defines the metadata attribute that enables an embedded resource in an assembly. This class cannot be inherited.
(in System.Web.dll)
'Usage
Dim instance As WebResourceAttribute
'Declaration
<AttributeUsageAttribute(AttributeTargets.Assembly, AllowMultiple := True)> _
<AspNetHostingPermissionAttribute(SecurityAction.LinkDemand, Level := AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class WebResourceAttribute _
Inherits Attribute
The WebResourceAttribute class is valid only when used on assembly declarations. It is used to enable a specified embedded resource in an assembly for use as a Web resource.
For more information on resources, see ASP.NET Web Page Resources Overview.
This section contains two code examples. The first code example demonstrates how to apply the WebResourceAttribute attribute to a namespace that defines a custom control, MyCustomControl. The second code example demonstrates how to use the MyCustomControl class in a Web page.
The following code example demonstrates how to apply the WebResourceAttribute attribute on a custom assembly to define an image Web resource and an HTML Web resource. The MyCustomControl class defines a composite control that uses the resources to set the value of the ImageUrl property of an Image control that is contained within the composite control and to set the HRef property of an HtmlAnchor control linking to the HTML resource.
Imports Microsoft.VisualBasic
Imports System
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.HtmlControls
Imports System.Web.UI.WebControls
<Assembly: WebResource("image1.gif", "image/jpeg")>
<Assembly: WebResource("help.htm", "text/html", PerformSubstitution:=True)>
Namespace Samples.AspNet.VB.Controls
Public Class MyCustomControl
Inherits Control
<System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
Protected Overrides Sub CreateChildControls()
' Create a new Image control.
Dim _img As New Image()
_img.ImageUrl = Me.Page.ClientScript.GetWebResourceUrl(GetType(MyCustomControl), "image1.jpg")
Me.Controls.Add(_img)
' Create a new Label control.
Dim _lab As New Label()
_lab.Text = "A composite control using the WebResourceAttribute class."
Me.Controls.Add(_lab)
' Create a new HtmlAnchor control linking to help.htm.
Dim a As HtmlAnchor = New HtmlAnchor()
a.HRef = Me.Page.ClientScript.GetWebResourceUrl(GetType(MyCustomControl), "help.htm")
a.InnerText = "help link"
Me.Controls.Add(New LiteralControl("<br />"))
Me.Controls.Add(a)
End Sub
End Class
End Namespace
The following code example demonstrates how to use the MyCustomControl class in a Web page.
<%@ Page Language="VB" %>
<%@ Register TagPrefix="AspNetSamples" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB.Controls" %>
<%@ Import Namespace="System.Reflection" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
' Get the assembly metatdata.
Dim clsType As Type = GetType(MyCustomControl)
Dim a As Assembly = clsType.Assembly
For Each attr As Attribute In Attribute.GetCustomAttributes(a)
'Check for WebResource attributes.
If attr.GetType() Is GetType(WebResourceAttribute) Then
Dim wra As WebResourceAttribute = CType(attr, WebResourceAttribute)
Response.Write("Resource in the assembly: " & wra.WebResource.ToString() & _
" with ContentType = " & wra.ContentType.ToString() & _
" and PerformsSubstitution = " & wra.PerformSubstitution.ToString() & "</br>")
End If
Next attr
End Sub
</script>
<html >
<head runat="server">
<title>WebResourceAttribute Example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<AspNetSamples:MyCustomControl id="MyCustomControl1" runat="server">
</AspNetSamples:MyCustomControl>
</div>
</form>
</body>
</html>
This example requires that you compile the Image1.jpg and Help.htm resources with the assembly that contains MyCustomControl. For more information, see, /resource (Embed Resource File to Output) (C# Compiler Options) or /resource (Visual Basic).
An example of an HTML Web resource that could be used in this example is shown next. Note the use of the WebResource syntax, which is used when you set the PerformSubstitution property to true for a Web resource.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html >
<head>
<title>Included Help Page</title>
</head>
<body>
<div>
<img alt="help image" src=<% = WebResource("image1.jpg") %> />
Included help file.
</div>
</body>
</html>
System..::.Object
System..::.Attribute
System.Web.UI..::.WebResourceAttribute
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0, 2.0
Reference
Other Resources
