This documentation is archived and is not being maintained.

HttpMethodAttribute Class

Applying this attribute to an XML Web service client using HTTP-GET or HTTP-POST, sets the types that serialize the parameters sent to an XML Web service method and read the response from the XML Web service method. This class cannot be inherited.

Namespace:  System.Web.Services.Protocols
Assembly:  System.Web.Services (in System.Web.Services.dll)

<AttributeUsageAttribute(AttributeTargets.Method)> _
Public NotInheritable Class HttpMethodAttribute _
	Inherits Attribute
Dim instance As HttpMethodAttribute

If an XML Web service client calls an XML Web service method using HTTP-GET, ReturnFormatter must be set to XmlReturnReader and ParameterFormatter set to UrlParameterWriter. XML Web service clients invoking a XML Web service using HTTP-POST must set ReturnFormatter to XmlReturnReader and ParameterFormatter to HtmlFormParameterWriter.

The following example is a proxy class generated by the Wsdl.exe utility for calling an XML Web service utility using HTTP-POST. The Wsdl.exe automatically supplies the correct types for ReturnFormatter and ParameterFormatter, along with specifying that the proxy class inherits from HttpPostClientProtocol.

Public Class MyUser
    Inherits System.Web.Services.Protocols.HttpPostClientProtocol

    Public Sub New()
        Me.Url = "" 
    End Sub 'New

    <HttpMethodAttribute(GetType(XmlReturnReader), GetType(HtmlFormParameterWriter))> _
    Public Function GetUserName() As UserName
        Return CType(Me.Invoke("GetUserName", Me.Url + "/GetUserName", New Object(0) {}), UserName)
    End Function 'GetUserName

    Public Function BeginGetUserName(callback As System.AsyncCallback, asyncState As Object) As System.IAsyncResult
        Return Me.BeginInvoke("GetUserName", Me.Url + "/GetUserName", New Object(0) {}, callback, asyncState)
    End Function 'BeginGetUserName

    Public Function EndGetUserName(asyncResult As System.IAsyncResult) As UserName
        Return CType(Me.EndInvoke(asyncResult), UserName)
    End Function 'EndGetUserName
End Class 'MyUser

<XmlRootAttribute(Namespace := "", IsNullable := True)> _
Public Class UserName
    Public Name As String 
    Public Domain As String 

End Class 'UserName
[System::Xml::Serialization::XmlRootAttribute(Namespace=S"", IsNullable=true)]
public __gc class UserName {

    String* Name;
    String* Domain;

public __gc class MyUser : public System::Web::Services::Protocols::HttpPostClientProtocol {

    MyUser() {
        this->Url = S"";

    [System::Web::Services::Protocols::HttpMethodAttribute(__typeof(System::Web::Services::Protocols::XmlReturnReader), __typeof(System::Web::Services::Protocols::HtmlFormParameterWriter))]
    UserName* GetUserName() {
        return (dynamic_cast<UserName*>(this->Invoke(S"GetUserName", (String::Concat( this->Url, S"/GetUserName" )), new Object*[0])));

    System::IAsyncResult* BeginGetUserName(System::AsyncCallback* callback, Object* asyncState) {
        return this->BeginInvoke(S"GetUserName", (String::Concat( this->Url, S"/GetUserName" )), new Object*[0], callback, asyncState);

    UserName* EndGetUserName(System::IAsyncResult* asyncResult) {
        return (dynamic_cast<UserName*>(this->EndInvoke(asyncResult)));


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, 1.1, 1.0