ResourceExpressionBuilder Class

ResourceExpressionBuilder Class


Provides code to the page parser for assigning property values on a control.

Namespace:   System.Web.Compilation
Assembly:  System.Web (in System.Web.dll)


public class ResourceExpressionBuilder : ExpressionBuilder


Initializes a new instance of the ResourceExpressionBuilder class.


Returns a value indicating whether an expression can be evaluated in a page that uses the no-compile feature.(Overrides ExpressionBuilder.SupportsEvaluate.)


Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_pubmethodEvaluateExpression(Object, BoundPropertyEntry, Object, ExpressionBuilderContext)

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethodGetCodeExpression(BoundPropertyEntry, Object, ExpressionBuilderContext)

Returns a code expression to evaluate during page execution.(Overrides ExpressionBuilder.GetCodeExpression(BoundPropertyEntry, Object, ExpressionBuilderContext).)


Serves as the default hash function. (Inherited from Object.)


Gets the Type of the current instance.(Inherited from Object.)


Creates a shallow copy of the current Object.(Inherited from Object.)


Returns an object that represents the parsed expression.

System_CAPS_pubmethodParseExpression(String, Type, ExpressionBuilderContext)

Returns an object that represents the parsed expression.(Overrides ExpressionBuilder.ParseExpression(String, Type, ExpressionBuilderContext).)


Returns a string that represents the current object.(Inherited from Object.)

The ResourceExpressionBuilder class creates code to retrieve resource values when the page is executed. A resource file typically contains information localized for a particular language or culture.

A resource expression takes the form <%$ Resources: ClassKey, ResourceKey %> within the page. The part of the expression before the colon (:) designates the type of expression builder to use, and the part after the colon signifies the class name and resource key. The preceding expression would retrieve the following value from a file named ClassKey.resx:

<data name="ResourceKey"><value xml:space="preserve">Hello!</value></data>

When the page parser encounters an expression with the Resources prefix, it creates an instance of the ResourceExpressionBuilder class. The ResourceExpressionBuilder class either evaluates the expression or generates code to return a value for the expression when the page is executed.

If the expression is encountered in a page that will be compiled, the ResourceExpressionBuilder object generates code that retrieves the specified value from the resource file. If the expression is encountered in a page that will not be compiled, the ResourceExpressionBuilder object returns the value from the resource file when the page is parsed.

The following code example retrieves the default currency from a resource file.

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

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">

<html xmlns="" >
<head runat="server">
    <title>Sales Page</title>
    <form id="form1" runat="server">
        All prices listed in 
        <asp:Literal ID="Literal1" runat="server" 
        Text="<%$ Resources: Financial, Currency %>" />.

This code reads the following value from a resource file named Financial.resx in the App_GlobalResources directory.

<data name="Currency"><value xml:space="preserve">US dollars</value></data>

.NET Framework
Available since 2.0

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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