Global and local variable

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Declaring variables

Global and local variable

Overview

Global variable

Global variable: Syntax

Local variable

Local variable: Syntax

Zombie local and global variables

See also

Global and local variable

Overview

Two types of variables are available:

Local variable: can only be used in the process where this variable was declared.
Global variable: can be used in all the processes related to the process in which this variable was declared.

Important: You must not declare two variables with the same name (especially a global variable and a local variable).

Global variable

Variables global to a project

Global variables declared in the "Initializing" event of a project can be used in all the events or processes:

of the project.
of the window or page (events of the window or page, of its controls and of the associated local procedures).
of the report (events of the report, of its controls and of the associated local procedures).

Availability of the variables in Browser code:

The server variables global to project are available in the browser codes for the following types only: Boolean, Integer, Real, String.
Tip: the global variables declared in a server code cannot be used to transmit information to the browser.
You have the ability to protect the variable global to the project so that it becomes unavailable on the browser side. To do so, use the Server only attribute when declaring the variable.
The following syntax must be used:

VariableName is VariableType <server only>

or:

VariableName is VariableType, server only

Example:

myvariable is int <server only>
myvariable1 is int, server only

Synchronization of variables in browser code:

By default, changes made to global variables in browser code are not carried over to the server.
When declaring a global variable, you can request its synchronization between browser and server. In this case the value assigned to a global variable in a browser code, can be retrieved later in a server code. To do so, use the browser synchronized attribute when declaring the variable.
The following syntax must be used:

VariableName is VariableType <browser synchronized>

or:

VariableName is VariableType, browser synchronized

Example:

myvariable is int <browser synchronized>
myvariable1 is int, browser synchronized

Variables global to a window

Global variables declared in the "Global declarations" event of a window can be used in all the events or processes:

of the window.
of the window controls.
of the local procedures associated with the window.

Limits:

The global variables of a window cannot be used by its sibling windows.
The global variables declared in a child window cannot be used in its parent window.
When the window where the variable was declared is closed, this variable cannot be used anymore.

Remark: Using a global variable in a child window of the declaration window

The variables declared global in a window are visible in the child windows of this window in the following cases:

If the External keyword is used to declare the variable in the child window.
If the variable name is prefixed by the window name.
If the variable is passed as a parameter to the child window.

Variables global to a page

Server code
Global variables declared in the "Global declarations" event of a page can be used in all the events or processes:

of the page.
of the page controls.
of the local procedures associated with the page.

When the page where the variable was declared is closed, this variable cannot be used anymore.

Availability of the variables in Browser code: The server variables global to a page are available in the browser codes of the page for the following types only: Boolean, Integer, Real, String.

Tip: the global variables declared in a server code cannot be used to transmit information to the browser.

Caution: the modifications made to these global variables in browser code are not carried over onto the server.

You can protect the page global variable to avoid making it available on the browser. To do so, use the Server only attribute when declaring the variable.
The following syntax must be used:

VariableName is VariableType <server only>

or:

VariableName is VariableType, server only

Example:

myvariable is int <server only>
myvariable1 is int, server only

Synchronization of variables in browser code:

By default, changes made to global variables in browser code are not carried over to the server.
When declaring a global variable, you can request its synchronization between browser and server. In this case the value assigned to a global variable in a browser code, can be retrieved later in a server code. To do so, use the browser synchronized attribute when declaring the variable.
The following syntax must be used:

VariableName is VariableType <browser synchronized>

or:

VariableName is VariableType, browser synchronized

Example:

myvariable is int <browser synchronized>
myvariable1 is int, browser synchronized

Browser code
Global variables declared in the "Page load (onLoad)" event can be used in all the browser events or processes:

of the page.
of the page controls.
of the local procedures associated with the page.

Availability of the variables in Server code: The browser variables global to a page are not available in the server codes of the page.

Tip: the global variables declared in a browser code can be used to exchange information between the different processes run on the browser.

Remarks:

The global browser variables cannot be initialized on the declaration line.
The global Browser variables can be initialized with the value of a global server variable (for the boolean, integer, real and string types only).
We recommend that you disable the "cache" of your browser when developing the WEBDEV application. Indeed, the global variables are translated into JavaScript in ".JS" files. If the "cache" is enabled, the tests of your pages may reload files corresponding to former values of variables.

To disable the cache of your browser (Microsoft Internet Explorer):

Find "Internet options" in one of the menus ("Edit", "Display" or "Tools" according to the version of Internet Explorer).
In the "General" tab, click "Parameters" in the "Temporary Internet Files" section.
Check "Whenever the page is visited".

Variables global to a report

Global variables declared in the "Opening" event of a report can be used in all the events or processes:

of the report.
of the report controls.
of the local procedures associated with the report.

Variables global to a set of procedures

Global variables declared in the "Declaration" event of a set of procedures can be used in all the events or processes:

of the different procedures in the set.
of the current project.

How to use a global variable from a component

Since the purpose of a component is to be stand-alone, no global variable of the project should be used from this one.

However, the recommended method is as follows:

create a global variable in the component.
in the component, create a procedure used to initialize these global variables.
from the "Initializing" event of the project and whenever the value of the global variables of the project is modified, call this procedure to assign a similar value to the global variables of the component.

Global variable: Syntax

Declaring one or more global variables

GLOBAL
<Global variables>

Details of syntax


GLOBAL	Beginning of declaration of global variables.
<Global variables>	Global variables to declare.

GLOBAL // All the declarations that follow are global variables
Index is int
CustomerName is string
Rate is real

LOCAL // All the declarations that follow are local variables
I is int
CustomerFName is string
Price is currency

Local variable

Local variables can only be used in the events or processes in which they are declared. Outside of these events or processes, local variables are unknown. These variables cannot be shared by several events or processes.

By default, a variable is local when it is declared.

In browser code, only the following types can be used to declare the local variables:

boolean,
int,
real,
string,
array of one of the previous types.

Local variable: Syntax

Declaring one or more local variables

[LOCAL]
<Local variables>

Details of syntax


LOCAL	Beginning of declaration of local variables. The LOCAL keyword is optional.
<Local variables>	Local variables to declare.

LOCAL // All the declarations that follow are local variables
I is int
CustomerFName is string
Price is currency

// All the declarations that follow are local variables
I is int
CustomerFName is string
Price is currency

Zombie local and global variables

A local or global variable can become obsolete. This allows you to in know that this element must not be used anymore (but that it is not deleted yet).

To declare a variable as being obsolete, all you have to do is use the <Zombie> extension attribute.

The syntax is as follows:

In this syntax, the optional comment keyword is used to specify the text that will be displayed in the compilation error associated with the obsolete variable.

Example:

CustomerFirstName is string <zombie comment = "Don't use anymore - use the Customer structure">