- Including constants
- Deploying the application
Extern (Reserved word)
In french: Externe
is used to:
- Include a text file containing WLanguage commands in an application (see syntax 1). This feature is only available in the initialization code of the project, in the declaration code of the global variables of a window/page and in the declaration code of a class.
- Declare an external object (see syntax 2).
// Syntax 1
// Include the "WinConst.wl" file that contains the standard Windows constants
pclObject is object dynamic
pclObject = document:getElementById("id_object")
<File name>: Character string
Name of text file containing the WLanguage code that must be included in an application. This is a standard text file, created by any text editor.
A full path can be specified (for example: "C:\WDProject\MyConst.wl"). If the path is not specified, the file will be sought:
- in the project directory,
- in the "Personal\Extern" directory of WINDEV, WEBDEV and WINDEV Mobile.
Including a text file with EXTERN has the same effect than copying a text file in the code editor.
<Name of external object>: Character string
Name of external object (variable, constant, ...) to declare.
EXTERN is used to declare a variable that will exist only when running the application.
- Including files is very useful to describe the constants common to several projects or used by the operating system. Use EXTERN to include in the code a file containing the common constants.
- Including files can only be performed in the following processes:
- Initialization code of project,
- Declaration code of global variables of window or page,
- Declaration code of class.
- Several files defining the constants are supplied (in the "\Personal\Extern" subdirectory of WINDEV, WEBDEV or WINDEV Mobile):
- "WinConst.wl": Standard Windows constants.
- "Limites.wl": Constants corresponding to the limits for the types of WINDEV, WEBDEV and WINDEV Mobile data.
- "ListeDefinitionHF.wl": HFSQL constants used for the log process (see Files handled by the log process).
- "Except.wl": Constants used to manage the exceptions.
- "KeyConst.wl": Standard Windows constants used for the keyboard keys. These constants can be used with KeyPressed in the optional WINDEV processes ("Key down" or "Key up") by using the _EVE.wParam variable.
Deploying the application
When installing the application on the client computer:
- If the path of the file is specified: The file must be installed in the specified directory.
- If the path of the file is not specified: By default, the file will be automatically installed in the directory of the project.
This page is also available for…