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Accessing XML Web Services in WKO Mode

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You can access and use any XML web service, even if that XML web service was not created using COM+ or even Microsoft Windows, as long as the XML Web Service publishes a WSDL description of its syntax. Just create an instance of the component by using the soap:wsdl=URL moniker, where URL is the URL of the WSDL description of the XML web service you want to access. This is the well-known object (WKO) mode of accessing XML web services.

The object's methods can be called without any special considerations. The XML web service is accessed via a SOAP query, and the response is interpreted transparently.

Component Services Administrative Tool

Does not apply.

Visual Basic

The following Microsoft Visual Basic code fragment illustrates the use of an XML web service in WKO mode.

Set Obj = GetObject("soap:wsdl=https://servername/vroot/progID.soap?WSDL")
output = Obj.Method(input)

In this code fragment, which illustrates the use of a component of a COM+ application that has been exposed as an XML web service, servername is the fully qualified domain name of the server offering the XML web service; vroot is the IIS virtual root directory from which the XML web service is exposed; and progID is the ProgID of the component you want to use.

C/C++

The following code fragment illustrates the use of an XML web service in WKO mode.

HRESULT hr = CoGetObject(
     L"soap:wsdl=https://servername/vroot/progID.soap?WSDL",
     pBindOptions,
     IID_IUnknown,
     (void**)&pIUnknown);
if (FAILED(hr)) throw(hr);

In this code fragment, which illustrates the use of a component of a COM+ application that has been exposed as an XML web service, servername is the fully qualified domain name of the server offering the XML web service; vroot is the IIS virtual root directory from which the XML web service is exposed; and progID is the ProgID of the component you want to use.

Remarks

When an XML web service is first accessed in WKO mode, COM+ generates a proxy client and compiles it in the background. This run-time generation and the lack of persistent connections in WKO mode results in significantly reduced performance in comparison to CAO mode.

Accessing XML Web Services in CAO Mode

COM+ SOAP Service Overview

Creating XML Web Services

Securing XML Web Services