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  • Assigning a Procedure variable
  • Multiple assignment of a Procedure variable
  • Runtime order of procedures
  • Passing parameters by reference or by value
  • Call to the procedures found in a Procedure variable
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Stored procedures
The Procedure type is used to handle by programming:
  • the procedures or methods found in the project.
  • the procedures or methods found in an internal component.
  • the procedures or methods found in an external component.
This type of variable is very useful, especially:
  • to optimize the time for starting the procedures. Using this type of variable allows you to replace the procedures run by ExecuteProcess.
  • to implement advanced algorithms (custom events, notifications, ...).
This help page presents:
Example
p is PROCEDURE
// Assign the Procedure variable with the "MyProcedure" procedure found in the project
p = MyProcedure
// Run the procedure
p(5)
// Equivalent to MyProcedure(5)
Remarks

Assigning a Procedure variable

A Procedure variable can be assigned with:
  • a procedure known in the project.
    The following syntax must be used:
    <Name of Procedure variable> = <Procedure>

    For example:
    p is PROCEDURE
    p = CheckExistence

    Notes:
    • The <Procedure> parameter must correspond to a procedure found in the project.
    • The <Procedure> parameter must not be enclosed in quotes.
    • The <Procedure> parameter must not be followed by call parameters.
    • The <Procedure> parameter must not correspond to the name of an internal procedure.
  • a class method.
    The following syntax must be used:
    <Name of Procedure Variable> = <Method>

    Notes:
    • The <Method> parameter must correspond to a method of current class or to a method of base class.
    • If <Method> is a method of instance, the code must be run in a method of instance of the class containing the method or in a derived class.
Other possible syntaxes
  • You also have the ability to copy the procedures of a Procedure variable into another Procedure variable. The syntax is as follows:
    <Name of Destination Procedure Variable> =
    <Name of Source Procedure Variable>

    Note: It is a copy of variable: any modification made to one of the variables will not be applied to the other one.
  • You also have the ability to find at runtime a procedure identified by its name and to assign it to a Procedure variable. In this case, the following syntax must be used:
    <Name of Procedure Variable> = <Procedure Name (with quotes)>

    Note: Using this syntax to assign a Procedure variable takes quite a long time because the name of the procedure is sought in all the procedures of the project.
  • Assignment by reference (<- operator)
    The assignment by taking reference forces the destination element to reference the same data area as the source element.
    Therefore, a Procedure variable can be handled by another Procedure variable. To do so, we must retrieve a reference on the Procedure variable itself. Any future modification made to one of the variables will be applied to the other one.
    The following syntax must be used:
    <Name of Destination Procedure Variable> <- <Name of Source Procedure Variable>

Multiple assignment of a Procedure variable

Several procedures or methods can be assigned to a Procedure variable via the "+=" operator. The different procedures will be called one after another.
For example:
p is PROCEDURE
p += Proc1
p += Proc2
Versions 18 and later
Note: To delete a procedure from a Procedure variable, you have the ability to use the "-=" operator.
For example:
p is PROCEDURE
p += Proc1
p += Proc2

...

p -= Proc2
New in version 18
Note: To delete a procedure from a Procedure variable, you have the ability to use the "-=" operator.
For example:
p is PROCEDURE
p += Proc1
p += Proc2

...

p -= Proc2
Note: To delete a procedure from a Procedure variable, you have the ability to use the "-=" operator.
For example:
p is PROCEDURE
p += Proc1
p += Proc2

...

p -= Proc2
Versions 19 and later

Runtime order of procedures

You have the ability to replace or insert a procedure before or after the other procedures in a Procedure element via ..Before and ..After.
Example:
p is PROCEDURE
p = MyProcedure
p..After = MyProcedureCalledAfter
p..Before = MyProcedureCalledBefore

// The order for calling the procedures will be:
// - MyProcedureCalledBefore
// - MyProcedure
// - MyProcedureCalledAfter
p()
New in version 19

Runtime order of procedures

You have the ability to replace or insert a procedure before or after the other procedures in a Procedure element via ..Before and ..After.
Example:
p is PROCEDURE
p = MyProcedure
p..After = MyProcedureCalledAfter
p..Before = MyProcedureCalledBefore

// The order for calling the procedures will be:
// - MyProcedureCalledBefore
// - MyProcedure
// - MyProcedureCalledAfter
p()

Runtime order of procedures

You have the ability to replace or insert a procedure before or after the other procedures in a Procedure element via ..Before and ..After.
Example:
p is PROCEDURE
p = MyProcedure
p..After = MyProcedureCalledAfter
p..Before = MyProcedureCalledBefore

// The order for calling the procedures will be:
// - MyProcedureCalledBefore
// - MyProcedure
// - MyProcedureCalledAfter
p()

Passing parameters by reference or by value

To handle a procedure as parameter of another procedure, you must use a typed parameter. The following syntax must be used:
  • to pass parameters by reference:
    PROCEDURE <ProcedureName>(MyProcedure is Procedure)
  • to pass parameters by value:
    PROCEDURE <ProcedureName>(LOCAL MyProcedure is Procedure)
The possible calls to the <ProcedureName> procedure are:
  • call while specifying a procedure known by the project: the following syntax must be used:
    ProcedureName(<Project Procedure>)

    Notes:
    • The <Project Procedure> parameter must correspond to a procedure found in the project.
    • The <Project Procedure> parameter must not be enclosed in quotes.
    • The <Project Procedure> parameter must not be followed by shortcuts.
  • call while specifying a class method: the following syntax must be used:
    ProcedureName(<Method>)

    Note: The <Method> parameter must correspond to a method of current class or to a method of base class.
  • call with reference to a procedure variable: the following syntax must be used:
    ProcedureName(<Name of Procedure variable>)
  • call with search at runtime for a procedure identified by its name: the following syntax must be used:
    ProcedureName(<Procedure name (with quotes)>)

Call to the procedures found in a Procedure variable

The call to the procedures found in a Procedure variable is performed by the standard syntax of procedures. This syntax is directly used on the Procedure variable with brackets containing 0, 1 or several parameters:
<Name of Procedure Variable> ([<Parameter 1> [, ...[, <Parameter N>]]])
Examples:
p1 is PROCEDURE
p1 = Proc1
p1()

p2 is PROCEDURE
p2 = Proc2
p2(1,2)
If the Procedure variable contains several procedures, all the procedures are run according to the order of assignments.
p3 is PROCEDURE
p3 += Proc3_1
p3 += Proc3_2
p3("parameter") // calls Proc3_1 and Proc3_2
Managing the return value
  • If the Procedure variable contains a single procedure, the call returns the return value of the procedure.
  • If the Procedure variable contains several procedures, the call returns the return value of the last procedure called.
See also
Minimum version required
  • Version 17
This page is also available for…
Comments
Exemplo Procedure
// Procedure - Duas Maneiras de Mandar Informacao

PROCEDURE rotina_teste(d_recebe_data is Date="", ...
s_recebe_texto is string="")
Info(d_recebe_data)
Info(s_recebe_texto)

//Chama Procedure
//d_manda_data is date=EDT_Date
//s_manda_texto is string=EDT_Text1
//
//rotina_teste(d_manda_data,s_manda_texto)

rotina_teste.d_recebe_data=EDT_Date
rotina_teste.s_recebe_texto=EDT_Text1
rotina_teste()
//Em vez de Mandar os parametros, dentro de uma linha
//mandei os parametros individual

//Blog com Video e Exemplo

http://windevdesenvolvimento.blogspot.com.br/2017/02/aula-1068-windev-comandos-13-procedure.html

https://www.youtube.com/watch?v=EPDTU569Pu4



De matos
21 Feb. 2017