:IF... :ELSE... :ENDIF

ScriptEigener Objekttyp in der Automation Engine Statements: They analyze an expression and depending on the result, they run statements.

Syntax

:IF Condition
[Statements]
[:ELSE]
[Other Statements]
:ENDIF

Comments

An IF statement is a control structure that you can use to process scripts depending on the result that a condition supplies. A condition is a logical expression.

When the condition applies (it is true), the statements are executed.

When the condition does not apply (it is false), the :ELSE statements are processed. When the IF block does not contain an :ELSE branch, it continues with the next line that follows the :ENDIF statement.

IF blocks can also be nested. The nesting depth is not limited.

IF blocks do not necessarily include ELSE branches.

When strings exceed 1024 characters, a difference in characters beyond the 1024th character will not be recognized by an :IF statement in the script. The comparing algorithm only checks the first 1024 characters of a string.

Using an OR keyword

To link a condition to several values or to link several individual conditions , you use OR as the keyword.

Conditions show the following structure:

For example:
:IF &DEP# = "EDP" OR "AE"

You can use up to 13 ORs in a condition.

Comparison operators

A condition contains one of the following comparison operators:

A numerical comparison takes place when both comparison values of a condition have a numerical value (data types signed, unsigned or float). A string comparison takes place in all other cases. Note that leading zeros are only ignored in numerical comparisons.

The following condition supplies "True":

:IF "0" = "0"

An alpha-numeric comparison takes place when there are no numerical values.

The following condition supplies "False":

:IF "0" = "abc"

Script lengths are not checked during the comparison process. The following condition supplies "True" because "S" comes before the "U" in the alphabet.

:IF "Smith" < "AE"

Note that you must define the script variables that you use in a condition beforehand.

Conditions that include the keyword OR several times can show various behaviors depending on the operator.

For example:
In the following example, one of the values must apply in order to meet the condition.

:IF &WD# = "MON" OR "TUW" OR "WED"

The following condition is only met if the variable does not comply to any of the three values.

:IF &WD# <> "THU" OR "FRI" OR "SAT"

Trailing Blank Spaces Are Not Considered

Trailing blank spaces are not considered in string comparisons. Therefore, blank strings always are equal independent on their length.

For example:

:set &a= 'a   '
:set &b= 'a'

:if &a = &b
:print 'true'
:endif

In this case, comparison of &a with &b would return true as trailing blanks are eliminated before the comparison.

Examples

The following examples show different ways of defining a condition. The examples 1 to 3 put a script variable into relation with one or more comparison values. The fourth example uses the return code of a function.

:IF &USER# = "TSOS"  
!... 
:ENDIF

:IF &DAT1# = &DAT2# OR " "  
!... 
:ENDIF

:IF GET_ATT(OO) = "J" 
!... 
:ENDIF

See also:

Script Elements - Script Structure and Processing
About Scripts
Script Elements - Alphabetical Listing
Script Elements - Ordered by function