HttpSimpleClientProtocol.Invoke(String, String, Object[]) Method

Reference

Definition

Namespace:: System.Web.Services.Protocols

Assembly:: System.Web.Services.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Invokes an XML Web service method using HTTP.

protected:
 System::Object ^ Invoke(System::String ^ methodName, System::String ^ requestUrl, cli::array <System::Object ^> ^ parameters);

protected object Invoke (string methodName, string requestUrl, object[] parameters);

member this.Invoke : string * string * obj[] -> obj

Protected Function Invoke (methodName As String, requestUrl As String, parameters As Object()) As Object

Parameters

methodName: String

The name of the XML Web service method in the derived class that is invoking the Invoke(String, String, Object[]) method.

requestUrl: String

The URL of the XML Web service method that the client is requesting.

parameters: Object[]

An array of objects containing the parameters to pass to the remote XML Web service. The order of the values in the array corresponds to the order of the parameters in the calling method of the derived class.

Returns

Object

An array of objects containing the return value and any by-reference or out parameters of the derived class method.

Exceptions

Exception

The request reached the server computer, but was not processed successfully.

Examples

The following code example is an ASP.NET Web Form, which calls an XML Web service named Math. Within the EnterBtn_Click function, the Web Form synchronously invokes the Add XML Web service method.

<%@ Page Language="VB" %>
<html>
    <script language="VB" runat="server">
    Sub EnterBtn_Click(Src As Object, E As EventArgs)
        Dim math As New Math()
        
        ' Call to Add XML Web service method.
        Dim result As Integer = math.Add(Convert.ToInt32(Num1.Text),Convert.ToInt32(Num2.Text))
        
        Total.Text = "Total: " & result.ToString()
    End Sub 'EnterBtn_Click
 
  </script>
 
    <body>
       <form action="MathClient.aspx" runat=server>
           
          Enter the two numbers you want to add and then press the Total button.
          <p>
          Number 1: <asp:textbox id="Num1" runat=server/>  +
          Number 2: <asp:textbox id="Num2" runat=server/> =
          <asp:button text="Total" Onclick="EnterBtn_Click" runat=server/>
          <p>
          <asp:label id="Total"  runat=server/>
          
       </form>
    </body>
 </html>

The following code example is a proxy class generated by the Web Services Description Language tool (Wsdl.exe) for the Math XML Web service below. Within the Add method of the proxy class, the Invoke method synchronously invokes the Add Web Service method.

#using <System.Web.Services.dll>
#using <System.Xml.dll>
#using <System.dll>

using namespace System::Diagnostics;
using namespace System::Xml::Serialization;
using namespace System;
using namespace System::Web::Services::Protocols;
using namespace System::Web::Services;

namespace MyMath
{

   [System::Web::Services::WebServiceBindingAttribute(Name="MathSoap",Namespace="http://tempuri.org/")]
   public ref class Math: public System::Web::Services::Protocols::SoapHttpClientProtocol
   {
   public:

      [System::Diagnostics::DebuggerStepThroughAttribute]
      Math()
      {
         this->Url = "http://www.contoso.com/math.asmx";
      }


      [System::Diagnostics::DebuggerStepThroughAttribute]
      [System::Web::Services::Protocols::SoapDocumentMethodAttribute("http://tempuri.org/Add",
      Use=System::Web::Services::Description::SoapBindingUse::Literal,
      ParameterStyle=System::Web::Services::Protocols::SoapParameterStyle::Wrapped)]
      int Add( int num1, int num2 )
      {
         array<Object^>^temp0 = {num1,num2};
         array<Object^>^results = this->Invoke( "Add", temp0 );
         return  *dynamic_cast<int^>(results[ 0 ]);
      }


      [System::Diagnostics::DebuggerStepThroughAttribute]
      System::IAsyncResult^ BeginAdd( int num1, int num2, System::AsyncCallback^ callback, Object^ asyncState )
      {
         array<Object^>^temp1 = {num1,num2};
         return this->BeginInvoke( "Add", temp1, callback, asyncState );
      }


      [System::Diagnostics::DebuggerStepThroughAttribute]
      int EndAdd( System::IAsyncResult^ asyncResult )
      {
         array<Object^>^results = this->EndInvoke( asyncResult );
         return  *dynamic_cast<int^>(results[ 0 ]);
      }

   };

}

namespace MyMath {
    using System.Diagnostics;
    using System.Xml.Serialization;
    using System;
    using System.Web.Services.Protocols;
    using System.Web.Services;

    [System.Web.Services.WebServiceBindingAttribute(Name="MathSoap", Namespace="http://tempuri.org/")]
    public class Math : System.Web.Services.Protocols.SoapHttpClientProtocol {

        [System.Diagnostics.DebuggerStepThroughAttribute()]
        public Math() {
            this.Url = "http://www.contoso.com/math.asmx";
        }

        [System.Diagnostics.DebuggerStepThroughAttribute()]
        [System.Web.Services.Protocols.SoapDocumentMethodAttribute("http://tempuri.org/Add", Use=System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle=System.Web.Services.Protocols.SoapParameterStyle.Wrapped)]
        public int Add(int num1, int num2) {
            object[] results = this.Invoke("Add", new object[] {num1,
                        num2});
            return ((int)(results[0]));
        }

        [System.Diagnostics.DebuggerStepThroughAttribute()]
        public System.IAsyncResult BeginAdd(int num1, int num2, System.AsyncCallback callback, object asyncState) {
            return this.BeginInvoke("Add", new object[] {num1,
                        num2}, callback, asyncState);
        }

        [System.Diagnostics.DebuggerStepThroughAttribute()]
        public int EndAdd(System.IAsyncResult asyncResult) {
            object[] results = this.EndInvoke(asyncResult);
            return ((int)(results[0]));
        }
    }
}

Namespace MyMath
    
    <System.Web.Services.WebServiceBindingAttribute(Name:="MathSoap", [Namespace]:="http://tempuri.org/")>  _
    Public Class Math
        Inherits System.Web.Services.Protocols.SoapHttpClientProtocol
        
        <System.Diagnostics.DebuggerStepThroughAttribute()>  _
        Public Sub New()
            MyBase.New
            Me.Url = "http://www.contoso.com/math.asmx"
        End Sub
        
        <System.Diagnostics.DebuggerStepThroughAttribute(),  _
         System.Web.Services.Protocols.SoapDocumentMethodAttribute("http://tempuri.org/Add", Use:=System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle:=System.Web.Services.Protocols.SoapParameterStyle.Wrapped)>  _
        Public Function Add(ByVal num1 As Integer, ByVal num2 As Integer) As Integer
            Dim results() As Object = Me.Invoke("Add", New Object() {num1, num2})
            Return CType(results(0),Integer)
        End Function
        
        <System.Diagnostics.DebuggerStepThroughAttribute()>  _
        Public Function BeginAdd(ByVal num1 As Integer, ByVal num2 As Integer, ByVal callback As System.AsyncCallback, ByVal asyncState As Object) As System.IAsyncResult
            Return Me.BeginInvoke("Add", New Object() {num1, num2}, callback, asyncState)
        End Function
        
        <System.Diagnostics.DebuggerStepThroughAttribute()>  _
        Public Function EndAdd(ByVal asyncResult As System.IAsyncResult) As Integer
            Dim results() As Object = Me.EndInvoke(asyncResult)
            Return CType(results(0),Integer)
        End Function
    End Class
End Namespace

The following code example is the Math XML Web service, from which the above proxy class was created.

<%@ WebService Language="C#" Class="Math"%>
 using System.Web.Services;
 using System;
 
 public class Math {
      [ WebMethod ]
      public int Add(int num1, int num2) {
          return num1+num2;
          }
 }

<%@ WebService Language="VB" Class="Math"%>
Imports System.Web.Services
Imports System

Public Class Math
    <WebMethod()> _
    Public Function Add(num1 As Integer, num2 As Integer) As Integer
        Return num1 + num2
    End Function 'Add
End Class 'Math

Remarks

The methodName parameter is used to find the types of the parameters and return values of the method that is invoking the Invoke method. It is also used to find custom attributes which may have been added to the method. HttpMethodAttribute and XmlElementAttribute provide additional information on the derived method that is required for the SOAP protocol.

Applies to

Share via