In most cases, a Web service is defined as an application that can be accessed via standard Internet protocols. More specifically, Web services allow several computers connected via Internet to interact.

Web services allow you to run procedures and processes on a remote Web server (.NET, SOAP or J2EE) from a client computer.

With WINDEV, these Web services can be used as client, via the SOAP protocol on HTTP (the standard Internet protocol for transferring HTML pages), with the SOAPxx, DotNetxx and J2EExx functions.

Regardless of the platform of the Web server (.NET, J2EE, ...), a Web service is accessible via the SOAP protocol.


	Remark	With WINDEV, you don't even have to be an expert in this field. A wizard takes care of ("almost") everything!

Practical example

A Webservice specific to this tutorial allows you to check the different operations that can be performed on a Webservice.

When integrated to the "WD Full Application" project, this Webservice is used to interrogate a supplier database to check whether a product is available in stock using its reference.

In a first time, the Webservice will be imported into the "WD Full Application" project then it will be used in the application to check the product availability from a Product form.

Importing a Webservice

Close the current project if necessary. The WINDEV home page is displayed.

In the home page, click "Tutorial" and select "Full application (Exercise)". The project is loaded.


	Answers	If you did not create the windows in the previous lessons, you can follow this lesson by opening a corrected project: in WINDEV's home page (Ctrl + <), click "Tutorial" and select "Full application (With windows)". A full corrected application project is also available: in WINDEV's home page (Ctrl + <), click "Tutorial" and select "Full application (Answer)"

Position (if necessary) on the "32-bit Windows executable" configuration: in the "Project explorer" pane, in the "Configurations" folder, double-click "Windows 32-bit executable".

To import a Webservice into the project:
1. On the "Project" pane, in the "Project" group, expand "Import" and select "A Webservice".
2. The import wizard starts. Go to the next step.
3. Specify the address into which the WSDL description of the Webservice must be imported:
  https://examples.webdev.info/WSTUTORIALV2_WEB/awws/WSTutorialV2.awws?wsdl
  
  Reminder: This Webservice is used to interrogate a supplier database to check the availability (stock) of a product from its reference.
4. Go to the next step. The Webservice is imported.
5. Validate the information window. The imported Webservice is in the "Imported Webservices" folder of the "Project explorer" tab pane.
6. In the "Project explorer" pane, expand the "Imported Webservices" folder.

Let's take a closer look at the information displayed in the "Project Explorer" pane:

The structure includes:

the Webservice name (WSTutorialV2 in this example),
the name of each function (ProductInStock in this example).

To find out how to call the Webservice, simply double-click the name of the function in the "Project explorer" pane. The code editor displays the function description, with the prototype for calling the function:

Consuming a Webservice

In our "WD Full Application" example, the call to the Webservice will be included in the tab used to see the list of products. A button "In stock?" is used to check whether the product displayed via the Webservice is available.

To use the Webservice:
1. Open the "WIN_Menu" window in the editor (double-click its name in the "Project explorer" pane, for example).
2. Add a Button control in the "List of products" tab pane:
  - On the "Creation" pane, in the "Usual controls" group, click .
  - Click below the "Modify " Button control in the window.
  - The control is automatically created.
3. Modify the characteristics of the control ("Description" from the popup menu). This control is named "BTN_InStock" and its caption is "In stock?".
4. Display the events associated with the control ("Code" from the popup menu).
5. Write the following WLanguage code in the "Click BTN_InStock" event:
  // Displays the Webservice response
  InfoBuild(...
  "Number of ""%1"" products in stock: %2", ...
  COL_Reference, ProductInStock(COL_Reference))
  Let's study this code:
  - The ProductInStock function of Webservice is called. This code uses the function prototype that was displayed beforehand in the code editor.
  - The response is formatted and displayed.
6. Close the code editor and save the window ( or Ctrl + S).

We are going to check the operating mode of Webservice:
1. Run the project test ( among the quick access buttons).
2. Click the "List of products" tab if necessary.
3. Select any product in the Table control and click "In stock?".
4. Validate the information window and close the application.