Procedura: associazione a un servizio Web usando il BindingSource Windows Form

Articolo
06/02/2023

Per associare un controllo Windows Form ai risultati ottenuti dalla chiamata a un servizio Web XML, è possibile usare un componente BindingSource. Questa procedura è simile al binding di un componente BindingSource a un tipo. È necessario creare un proxy lato client contenente i metodi e tipi esposti dal servizio Web. Si genera un proxy lato client direttamente dal servizio Web (asmx) o dal file Web Services Description Language (WSDL). Inoltre, il proxy lato client deve esporre i campi dei tipi complessi usati dal servizio Web come proprietà pubbliche. Quindi si associa BindingSource a uno dei tipi esposti nel proxy del servizio Web.

Per creare ed eseguire il binding a un proxy lato client

Creare un Windows Form nella directory scelta, con uno spazio dei nomi appropriato.
Aggiungere un componente BindingSource al form.
Aprire il prompt dei comandi di Windows Software Development Kit (SDK) e passare alla stessa directory in cui si trova il modulo.
Tramite lo strumento WSDL immettere wsdl e l'URL del file asmx o WSDL per il servizio Web, seguito dallo spazio dei nomi dell'applicazione e, facoltativamente, dal linguaggio in uso.

Nell'esempio di codice seguente viene usato il servizio Web che si trova in http://webservices.eraserver.net/zipcoderesolver/zipcoderesolver.asmx. Ad esempio, per C# digitare wsdl http://webservices.eraserver.net.zipcoderesolver/zipcoderesolver.asmx /n:BindToWebService e per Visual Basic digitare wsdl http://webservices.eraserver.net.zipcoderesolver/zipcoderesolver.asmx /n:BindToWebService /language:VB. Passando il percorso come argomento allo strumento WSDL, verrà generato un proxy lato client nella stessa directory e nello stesso spazio dei nomi dell'applicazione, nel linguaggio specificato. Se si usa Visual Studio, aggiungere il file al progetto.

Selezionare un tipo nel proxy lato client a cui eseguire il binding.

In genere si tratta di un tipo restituito da un metodo offerto dal servizio Web. I campi del tipo scelto devono essere esposti come proprietà pubbliche ai fini dell'associazione.

    [System::SerializableAttribute, System::Xml::Serialization::XmlTypeAttribute(
        Namespace="http://webservices.eraserver.net/")]
    public ref class USPSAddress
    {

private:
        String^ streetField;

        String^ cityField;

        String^ stateField;

        String^ shortZIPField;

        String^ fullZIPField;


public:
        property String^ Street    
        {
            String^ get()
            {
                return this->streetField;
            }
            void set( String^ value )
            {
                this->streetField = value;
            }
        }


        property String^ City    
        {
            String^ get()
            {
                return this->cityField;
            }
            void set( String^ value )
            {
                this->cityField = value;
            }
        }
        property String^ State    
        {
            String^ get()
            {
                return this->stateField;
            }
            void set( String^ value )
            {
                this->stateField = value;
            }
        }

        property String^ ShortZIP    
        {
            String^ get()
            {
                return this->shortZIPField;
            }
            void set( String^ value )
            {
                this->shortZIPField = value;
            }
        }

        property String^ FullZIP    
        {
            String^ get()
            {
                return this->fullZIPField;
            }
            void set( String^ value )
            {
                this->fullZIPField = value;
            }
        }
    };

[System.SerializableAttribute, System.Xml.Serialization.XmlTypeAttribute(
    Namespace="http://webservices.eraserver.net/")]
public class USPSAddress
{

    private string streetField;

    private string cityField;

    private string stateField;

    private string shortZIPField;

    private string fullZIPField;

    public string Street
    {
        get
        {
            return this.streetField;
        }
        set
        {
            this.streetField = value;
        }
    }

    public string City
    {
        get
        {
            return this.cityField;
        }
        set
        {
            this.cityField = value;
        }
    }

    public string State
    {
        get
        {
            return this.stateField;
        }
        set
        {
            this.stateField = value;
        }
    }

    public string ShortZIP
    {
        get
        {
            return this.shortZIPField;
        }
        set
        {
            this.shortZIPField = value;
        }
    }

    public string FullZIP
    {
        get
        {
            return this.fullZIPField;
        }
        set
        {
            this.fullZIPField = value;
        }
    }
}

<System.SerializableAttribute(), _
 System.Xml.Serialization.XmlTypeAttribute( _
    [Namespace]:="http://webservices.eraserver.net/")> _
Public Class USPSAddress

    Private streetField As String

    Private cityField As String

    Private stateField As String

    Private shortZIPField As String

    Private fullZIPField As String


    Public Property Street() As String
        Get
            Return Me.streetField
        End Get
        Set(ByVal value As String)
            Me.streetField = value
        End Set
    End Property


    Public Property City() As String
        Get
            Return Me.cityField
        End Get
        Set(ByVal value As String)
            Me.cityField = value
        End Set
    End Property

    Public Property State() As String
        Get
            Return Me.stateField
        End Get
        Set(ByVal value As String)
            Me.stateField = value
        End Set
    End Property


    Public Property ShortZIP() As String
        Get
            Return Me.shortZIPField
        End Get
        Set(ByVal value As String)
            Me.shortZIPField = value
        End Set
    End Property


    Public Property FullZIP() As String
        Get
            Return Me.fullZIPField
        End Get
        Set(ByVal value As String)
            Me.fullZIPField = value
        End Set
    End Property
End Class

Impostare la proprietà DataSource di BindingSource sul tipo desiderato contenuto nel proxy lato client del servizio Web.

BindingSource1->DataSource = USPSAddress::typeid;

BindingSource1.DataSource = typeof(USPSAddress);

BindingSource1.DataSource = GetType(USPSAddress)

Per associare i controlli all'oggetto BindingSource associato a un servizio Web

Associare i controlli a BindingSource, passando la proprietà pubblica del tipo di servizio Web scelto come parametro.

textBox1->DataBindings->Add("Text", this->BindingSource1, "FullZIP", true);

textBox1.DataBindings.Add("Text", this.BindingSource1, "FullZIP", true);

textBox1.DataBindings.Add("Text", Me.BindingSource1, "FullZIP", True)

Esempio

Il seguente esempio di codice mostra come associare un componente BindingSource a un servizio Web e quindi come associare una casella di testo al componente BindingSource. Quando si fa clic sul pulsante, viene chiamato un metodo del servizio Web e i risultati appaiono in textbox1.

#using <System.Windows.Forms.dll>
#using <System.dll>
#using <System.Drawing.dll>
#using <System.Web.Services.dll>
#using <System.Xml.dll>

using namespace System;
using namespace System::Collections::Generic;
using namespace System::ComponentModel;
using namespace System::Drawing;
using namespace System::Windows::Forms;
 
namespace BindToWebService {

    [System::SerializableAttribute, System::Xml::Serialization::XmlTypeAttribute(
        Namespace="http://webservices.eraserver.net/")]
    public ref class USPSAddress
    {

private:
        String^ streetField;

        String^ cityField;

        String^ stateField;

        String^ shortZIPField;

        String^ fullZIPField;


public:
        property String^ Street    
        {
            String^ get()
            {
                return this->streetField;
            }
            void set( String^ value )
            {
                this->streetField = value;
            }
        }


        property String^ City    
        {
            String^ get()
            {
                return this->cityField;
            }
            void set( String^ value )
            {
                this->cityField = value;
            }
        }
        property String^ State    
        {
            String^ get()
            {
                return this->stateField;
            }
            void set( String^ value )
            {
                this->stateField = value;
            }
        }

        property String^ ShortZIP    
        {
            String^ get()
            {
                return this->shortZIPField;
            }
            void set( String^ value )
            {
                this->shortZIPField = value;
            }
        }

        property String^ FullZIP    
        {
            String^ get()
            {
                return this->fullZIPField;
            }
            void set( String^ value )
            {
                this->fullZIPField = value;
            }
        }
    };


    [System::Web::Services::WebServiceBindingAttribute(Name="ZipCodeResolverSoap",
        Namespace="http://webservices.eraserver.net/")]
    public ref class ZipCodeResolver:
        public System::Web::Services::Protocols::SoapHttpClientProtocol

    {
        
public:
        ZipCodeResolver() : SoapHttpClientProtocol()
        {        
            this->Url = 
                "http://webservices.eraserver.net/zipcoderesolver/zipcoderesolver.asmx";
        }

    
        //''<remarks/>
        [System::Web::Services::Protocols::SoapDocumentMethodAttribute
            ("http://webservices.eraserver.net/CorrectedAddressXml", 
            RequestNamespace="http://webservices.eraserver.net/", 
            ResponseNamespace="http://webservices.eraserver.net/", 
            Use=System::Web::Services::Description::SoapBindingUse::Literal, 
            ParameterStyle=System::Web::Services::Protocols::SoapParameterStyle::Wrapped)]
        USPSAddress^ CorrectedAddressXml(String^ accessCode, 
            String^ address, String^ city, String^ state)
        {
            array<Object^>^ results = this->Invoke("CorrectedAddressXml", 
                gcnew array<Object^>{accessCode, address, city, state});
            return ((USPSAddress^) results[0]);
        }

        //''<remarks/>
        System::IAsyncResult^ BeginCorrectedAddressXml(String^ accessCode,
            String^ address, String^ city, String^ state, 
            System::AsyncCallback^ callback, Object^ asyncState)
        {

            return this->BeginInvoke("CorrectedAddressXml", 
                gcnew array<Object^>{accessCode, address, city, state}, callback, asyncState);
        }


        USPSAddress^ EndCorrectedAddressXml(System::IAsyncResult^ asyncResult)
        {
            array<Object^>^ results = this->EndInvoke(asyncResult);
            return ((USPSAddress^) results[0]);
        }

    };

    ref class Form1: public Form
    {
public:
        [STAThread]
        static void Main()
        {
            Application::EnableVisualStyles();
            Application::Run(gcnew Form1());
        }

private:
        BindingSource^ BindingSource1;

        TextBox^ textBox1;

        TextBox^ textBox2;

        Button^ button1;


public:
        Form1()
        {
            this->Load += gcnew EventHandler(this, &Form1::Form1_Load);
            textBox1->Location = System::Drawing::Point(118, 131);
            textBox1->ReadOnly = true;
            button1->Location = System::Drawing::Point(133, 60);
            button1->Click += gcnew EventHandler(this, &Form1::button1_Click);
            button1->Text = "Get zipcode";
            ClientSize = System::Drawing::Size(292, 266);
            Controls->Add(this->button1);
            Controls->Add(this->textBox1);
                        BindingSource1 = gcnew BindingSource();
                        textBox1 = gcnew TextBox();
                        textBox2 = gcnew TextBox();
                        button1 = gcnew Button();
        }

private:
        void button1_Click(Object^ sender, EventArgs^ e)
        {
            textBox1->Text = "Calling Web service..";
            ZipCodeResolver^ resolver = gcnew ZipCodeResolver();
            BindingSource1->Add(resolver->CorrectedAddressXml("0",
                    "One Microsoft Way", "Redmond", "WA"));
                        
        }

public:
        void Form1_Load(Object^ sender, EventArgs^ e)
        {
            BindingSource1->DataSource = USPSAddress::typeid;
            textBox1->DataBindings->Add("Text", this->BindingSource1, "FullZIP", true);
        }
    };




    public ref class CorrectedAddressXmlCompletedEventArgs:
    public System::ComponentModel::AsyncCompletedEventArgs

    {
private:
        array<Object^>^ results;

internal:
        CorrectedAddressXmlCompletedEventArgs(array<Object^>^ results,
            System::Exception^ exception, bool cancelled, Object^ userState) :
            AsyncCompletedEventArgs(exception, cancelled, userState)
        {        
            this->results = results;
        }


public:
        property USPSAddress^ Result    
        {
            USPSAddress^ get()
            {
                this->RaiseExceptionIfNecessary();
                return ((USPSAddress^) this->results[0]);
            }
        }

     delegate void CorrectedAddressXmlCompletedEventHandler(Object^ sender,
        CorrectedAddressXmlCompletedEventArgs^ args);

    };
}

int main()
{
    BindToWebService::Form1::Main();
    return 1;
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Windows.Forms;

namespace BindToWebService {
    class Form1: Form

    {
        [STAThread]
        public static void Main()
        {
            Application.EnableVisualStyles();
            Application.Run(new Form1());
        }

        private BindingSource BindingSource1 = new BindingSource();
        private TextBox textBox1 = new TextBox();
        private TextBox textBox2 = new TextBox();
        private Button button1 = new Button();

        public Form1()
        {
            this.Load += new EventHandler(Form1_Load);
            textBox1.Location = new System.Drawing.Point(118, 131);
            textBox1.ReadOnly = true;
            button1.Location = new System.Drawing.Point(133, 60);
            button1.Click += new EventHandler(button1_Click);
            button1.Text = "Get zipcode";
            ClientSize = new System.Drawing.Size(292, 266);
            Controls.Add(this.button1);
            Controls.Add(this.textBox1);
        }

        private void button1_Click(object sender, EventArgs e)
        {

            textBox1.Text = "Calling Web service..";
            ZipCodeResolver resolver = new ZipCodeResolver();
            BindingSource1.Add(resolver.CorrectedAddressXml("0",
                    "One Microsoft Way", "Redmond", "WA"));
        }

        public void Form1_Load(object sender, EventArgs e)
        {
            BindingSource1.DataSource = typeof(USPSAddress);
            textBox1.DataBindings.Add("Text", this.BindingSource1, "FullZIP", true);
        }
    }

    [System.Web.Services.WebServiceBindingAttribute(Name="ZipCodeResolverSoap",
        Namespace="http://webservices.eraserver.net/")]
    public class ZipCodeResolver:
        System.Web.Services.Protocols.SoapHttpClientProtocol

    {
        
        public ZipCodeResolver() : base()
        {
            this.Url =
                "http://webservices.eraserver.net/zipcoderesolver/zipcoderesolver.asmx";
        }

        //''<remarks/>
        [System.Web.Services.Protocols.SoapDocumentMethodAttribute
            ("http://webservices.eraserver.net/CorrectedAddressXml",
            RequestNamespace="http://webservices.eraserver.net/",
            ResponseNamespace="http://webservices.eraserver.net/",
            Use=System.Web.Services.Description.SoapBindingUse.Literal,
            ParameterStyle=System.Web.Services.Protocols.SoapParameterStyle.Wrapped)]
        public USPSAddress CorrectedAddressXml(string accessCode,
            string address, string city, string state)
        {
            object[] results = this.Invoke("CorrectedAddressXml",
                new object[]{accessCode, address, city, state});
            return ((USPSAddress) results[0]);
        }

        //''<remarks/>
        public System.IAsyncResult BeginCorrectedAddressXml(string accessCode,
            string address, string city, string state,
            System.AsyncCallback callback, object asyncState)
        {

            return this.BeginInvoke("CorrectedAddressXml",
                new object[]{accessCode, address, city, state}, callback, asyncState);
        }

        public USPSAddress EndCorrectedAddressXml(System.IAsyncResult asyncResult)
        {
            object[] results = this.EndInvoke(asyncResult);
            return ((USPSAddress) results[0]);
        }
    }

    [System.SerializableAttribute, System.Xml.Serialization.XmlTypeAttribute(
        Namespace="http://webservices.eraserver.net/")]
    public class USPSAddress
    {

        private string streetField;

        private string cityField;

        private string stateField;

        private string shortZIPField;

        private string fullZIPField;

        public string Street
        {
            get
            {
                return this.streetField;
            }
            set
            {
                this.streetField = value;
            }
        }

        public string City
        {
            get
            {
                return this.cityField;
            }
            set
            {
                this.cityField = value;
            }
        }

        public string State
        {
            get
            {
                return this.stateField;
            }
            set
            {
                this.stateField = value;
            }
        }

        public string ShortZIP
        {
            get
            {
                return this.shortZIPField;
            }
            set
            {
                this.shortZIPField = value;
            }
        }

        public string FullZIP
        {
            get
            {
                return this.fullZIPField;
            }
            set
            {
                this.fullZIPField = value;
            }
        }
    }

    public delegate void CorrectedAddressXmlCompletedEventHandler(object sender,
        CorrectedAddressXmlCompletedEventArgs args);

    public class CorrectedAddressXmlCompletedEventArgs:
    System.ComponentModel.AsyncCompletedEventArgs

    {
        private object[] results;

        internal CorrectedAddressXmlCompletedEventArgs(object[] results,
            System.Exception exception, bool cancelled, object userState) :
            base(exception, cancelled, userState)
        {
            this.results = results;
        }

        public USPSAddress Result
        {
            get
            {
                this.RaiseExceptionIfNecessary();
                return ((USPSAddress) this.results[0]);
            }
        }
    }
 }

Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Drawing
Imports System.Windows.Forms

Namespace BindToWebService
    Class Form1
        Inherits Form

        <STAThread()> _
        Shared Sub Main()
            Application.EnableVisualStyles()
            Application.Run(New Form1())
        End Sub

        Private BindingSource1 As New BindingSource()
        Private textBox1 As New TextBox()
        Private textBox2 As New TextBox()
        Private WithEvents button1 As New Button()

        Public Sub New()

            textBox1.Location = New System.Drawing.Point(118, 131)
            textBox1.ReadOnly = True
            button1.Location = New System.Drawing.Point(133, 60)
            button1.Text = "Get zipcode"
            ClientSize = New System.Drawing.Size(292, 266)
            Controls.Add(Me.button1)
            Controls.Add(Me.textBox1)
        End Sub

        Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
            Handles button1.Click

            textBox1.Text = "Calling Web service.."
            Dim resolver As New ZipCodeResolver()
            BindingSource1.Add(resolver.CorrectedAddressXml("0", "One Microsoft Way", "Redmond", "WA"))

        End Sub


        Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
            BindingSource1.DataSource = GetType(USPSAddress)
            textBox1.DataBindings.Add("Text", Me.BindingSource1, "FullZIP", True)
        End Sub

    End Class

    <System.Diagnostics.DebuggerStepThroughAttribute(), _
     System.ComponentModel.DesignerCategoryAttribute("code"), _
     System.Web.Services.WebServiceBindingAttribute(Name:="ZipCodeResolverSoap", _
        [Namespace]:="http://webservices.eraserver.net/")> _
    Public Class ZipCodeResolver
        Inherits System.Web.Services.Protocols.SoapHttpClientProtocol

        Private CorrectedAddressXmlOperationCompleted As _
            System.Threading.SendOrPostCallback


        Public Sub New()
            MyBase.New()
            Me.Url = _
                "http://webservices.eraserver.net/zipcoderesolver/zipcoderesolver.asmx"
        End Sub


        Public Event CorrectedAddressXmlCompleted As _
            CorrectedAddressXmlCompletedEventHandler

        <System.Web.Services.Protocols.SoapDocumentMethodAttribute( _
            "http://webservices.eraserver.net/CorrectedAddressXml", _
            RequestNamespace:="http://webservices.eraserver.net/", _
            ResponseNamespace:="http://webservices.eraserver.net/", _
            Use:=System.Web.Services.Description.SoapBindingUse.Literal, _
            ParameterStyle:=System.Web.Services.Protocols.SoapParameterStyle.Wrapped)> _
        Public Function CorrectedAddressXml(ByVal accessCode As String, _
            ByVal address As String, ByVal city As String, ByVal state As String) _
            As USPSAddress
            Dim results() As Object = Me.Invoke("CorrectedAddressXml", _
                New Object() {accessCode, address, city, state})
            Return CType(results(0), USPSAddress)
        End Function

        '''<remarks/>
        Public Function BeginCorrectedAddressXml(ByVal accessCode As String, _
            ByVal address As String, ByVal city As String, ByVal state As String, _
            ByVal callback As System.AsyncCallback, ByVal asyncState As Object) _
            As System.IAsyncResult

            Return Me.BeginInvoke("CorrectedAddressXml", _
                New Object() {accessCode, address, city, state}, callback, asyncState)
        End Function

        Public Function EndCorrectedAddressXml(ByVal asyncResult _
            As System.IAsyncResult) As USPSAddress
            Dim results() As Object = Me.EndInvoke(asyncResult)
            Return CType(results(0), USPSAddress)
        End Function
    End Class

    <System.SerializableAttribute(), _
     System.Xml.Serialization.XmlTypeAttribute( _
        [Namespace]:="http://webservices.eraserver.net/")> _
    Public Class USPSAddress

        Private streetField As String

        Private cityField As String

        Private stateField As String

        Private shortZIPField As String

        Private fullZIPField As String


        Public Property Street() As String
            Get
                Return Me.streetField
            End Get
            Set(ByVal value As String)
                Me.streetField = value
            End Set
        End Property


        Public Property City() As String
            Get
                Return Me.cityField
            End Get
            Set(ByVal value As String)
                Me.cityField = value
            End Set
        End Property

        Public Property State() As String
            Get
                Return Me.stateField
            End Get
            Set(ByVal value As String)
                Me.stateField = value
            End Set
        End Property


        Public Property ShortZIP() As String
            Get
                Return Me.shortZIPField
            End Get
            Set(ByVal value As String)
                Me.shortZIPField = value
            End Set
        End Property


        Public Property FullZIP() As String
            Get
                Return Me.fullZIPField
            End Get
            Set(ByVal value As String)
                Me.fullZIPField = value
            End Set
        End Property
    End Class

    Public Delegate Sub CorrectedAddressXmlCompletedEventHandler(ByVal sender As Object, _
         ByVal args As CorrectedAddressXmlCompletedEventArgs)

    Public Class CorrectedAddressXmlCompletedEventArgs
        Inherits System.ComponentModel.AsyncCompletedEventArgs

        Private results() As Object

        Friend Sub New(ByVal results() As Object, ByVal exception As System.Exception, _
            ByVal cancelled As Boolean, ByVal userState As Object)
            MyBase.New(exception, cancelled, userState)
            Me.results = results
        End Sub

        Public ReadOnly Property Result() As USPSAddress
            Get
                Me.RaiseExceptionIfNecessary()
                Return CType(Me.results(0), USPSAddress)
            End Get
        End Property
    End Class

End Namespace

Compilazione del codice

Questo è un esempio completo che include un metodo Main e una versione abbreviata del codice del proxy lato client.

L'esempio presenta i requisiti seguenti:

Riferimenti agli assembly System, System.Drawing, System.Web.Services, System.Windows.Forms e System.Xml.

Procedura: associazione a un servizio Web usando il BindingSource Windows Form

Per creare ed eseguire il binding a un proxy lato client

Per associare i controlli all'oggetto BindingSource associato a un servizio Web

Esempio

Compilazione del codice

Vedi anche

Commenti e suggerimenti

Risorse aggiuntive