@Page Attributes

Ref.: MSDN

Defines page-specific (.aspx file) attributes used by the ASP.NET page parser and compiler.

<%@ Page attribute="value" [attribute="value"...] %>  

Attributes

AspCompat

When set to true, this allows the page to be executed on a single-threaded apartment (STA) thread. This allows the page to call STA components, such as a component developed with Microsoft Visual Basic 6.0. Setting this attribute to true also allows the page to call COM+ 1.0 components that require access to unmanaged Active Server Pages (ASP) built-in objects. These are accessible through the ObjectContext object or the OnStartPage method. The default is false.

Note   Setting this attribute to true can cause your page's performance to degrade. For more information, see the Remarks section.

AutoEventWireup

Indicates whether the page's events are autowired. true if event autowiring is enabled; otherwise, false. The default is true. For more information, see Web Server Control Event Model.

Buffer

Determines whether HTTP response buffering is enabled. true if page buffering is enabled; otherwise, false. The default is true.

ClassName

Specifies the class name for the page that will be dynamically compiled automatically when the page is requested. This value can be any valid class name but should not include a namespace.

ClientTarget

Indicates the target user agent for which ASP.NET server controls should render content. This value can be any valid user agent or alias.

CodeBehind

Specifies the name of the compiled file that contains the class associated with the page. This attribute is used by the Visual Studio .NET Web Forms designer. It tells the designer where to find the page class so that the designer can create an instance of it for you to work with at design time. For example, if you create a Web Forms page in Visual Studio called WebForm1, the designer will assign the Codebehind attribute the value of WebForm1.aspx.vb, for Visual Basic, or WebForm1.aspx.cs, for C#. This attribute is not used at run time.

CodePage

Indicates the code page value for the response.

Note   If you created your Web Forms page using a code page other than the default code page of the Web server on which the page will run, you must set this attribute. The value you enter should be the code page for the computer on which you created the page. For more information about code pages, search the Microsoft Developers Network (MSDN) at http://msdn.microsoft.com.

CompilerOptions

A string containing compiler options used to compile the page. In C# and Visual Basic .NET, this is a sequence of compiler command-line switches.

ContentType

Defines the HTTP content type of the response as a standard MIME type. Supports any valid HTTP content-type string. For a list of possible values, search for MIME in MSDN at http://www.microsoft.com/technet.

Culture

Indicates the culture setting for the page. For information about culture settings and possible culture values, see the CultureInfo class.

Debug

Indicates whether the page should be compiled with debug symbols. true if the page should be compiled with debug symbols; otherwise, false.

Description

Provides a text description of the page. This value is ignored by the ASP.NET parser.

EnableSessionState

Defines session-state requirements for the page. true if session state is enabled; ReadOnly if session state can be read but not changed; otherwise, false. The default istrue. These values are case-insensitive. For more information, see Session State.

EnableViewState

Indicates whether view state is maintained across page requests. true if view state is maintained; otherwise, false. The default is true.

EnableViewStateMac

Indicates that ASP.NET should run a machine authentication check (MAC) on the page's view state when the page is posted back from the client. true if view state should be MAC checked; otherwise, false. The default is false.

Note   A view-state MAC is an encrypted version of the hidden variable that a page's view state is persisted to when sent to the browser. When you set this attribute to true, the encrypted view state is checked to verify that it has not been tampered with on the client.

ErrorPage

Defines a target URL for redirection if an unhandled page exception occurs.

Explicit

Determines whether the page is compiled using the Visual Basic Option Explicit mode. true indicates that the Visual Basic explicit compile option is enabled and that all variables must be declared using a Dim, Private, Public, or ReDim statement; otherwise, false. The default is false.

Note   This attribute is ignored by languages other than Visual Basic .NET. Also, this option is set to true in the Machine.config configuration file. For more information, see Machine Configuration Files.

Inherits

Defines a code-behind class for the page to inherit. This can be any class derived from the Page class. For information about code-behind classes, see Web Forms Code Model.

Language

Specifies the language used when compiling all inline rendering (<% %> and <%= %>) and code declaration blocks within the page. Values can represent any .NET-supported language, including Visual Basic, C#, or JScript .NET.

LCID

Defines the locale identifier for the Web Forms page.

Note   The locale identifier is a 32-bit value that uniquely defines a locale. ASP.NET uses the default locale of the Web server unless you specify a different locale for a Web Forms page by using this attribute. For more information about locales, search MSDN at http://msdn.microsoft.com.

ResponseEncoding

Indicates the response encoding of page content. Supports values from the Encoding.GetEncoding method.

Src

Specifies the source file name of the code-behind class to dynamically compile when the page is requested. You can choose to include programming logic for your page either in a code-behind class or in a code declaration block in the .aspx file.

Note   RAD designers, such as Visual Studio .NET, do not use this attribute. Instead, they precompile code-behind classes and then use the Inherits attribute.

SmartNavigation

Indicates whether the page supports the smart navigation feature of Internet Explorer 5.5 or later..

Note   For more information about smart navigation, see the Remarks section.

Strict

Indicates that the page should be compiled using the Visual Basic Option Strict mode. true if Option Strict is enabled; otherwise, false. The default is false.

Note   This attribute is ignored by languages other than Visual Basic .NET.

Trace

Indicates whether tracing is enabled. true if tracing is enabled; otherwise, false. The default is false. For more information, see ASP.NET Trace.

TraceMode

Indicates how traces messages are to be displayed for the page when tracing is enabled. Possible values are SortByTime and SortByCategory. The default, when tracing is enabled, is SortByTime. For more information about tracing, see ASP.NET Trace.

Transaction

Indicates whether transactions are supported on the page. Possible values are Disabled, NotSupported, Supported, Required, and RequiresNew. The default is Disabled.

UICulture

Specifies the UI culture setting to use for the page. Supports any valid UI culture value.

ValidateRequest

Indicates whether request validation should occur. If true, request validation checks all input data against a hard-coded list of potentially dangerous values. If a match occurs, an HttpRequestValidationException Class is thrown. The default is true.

This feature is enabled in the machine configuration file (Machine.config). You can disable it in your application configuration file (Web.config) or on the page by setting this attribute to false.

Note   This functionality helps reduce the risk of cross-site scripting attacks for straightforward pages and ASP.NET applications. An application that does not properly validate user input can suffer from many types of malformed input attacks, including cross-site scripting and SQL Server injection attacks. There is no substitute for carefully evaluating all forms of input in an application and making sure that they are either properly validated or encoded, or that the application is escaped prior to manipulating data or sending information back to the client. For more information about cross-site scripting, see http://www.cert.org/advisories/CA-2000-02.html.

WarningLevel

Indicates the compiler warning level at which you want the compiler to abort compilation for the page. Possible values are 0 through 4. For more information, see theCompilerParameters.WarningLevel Property property.