Difference between revisions of "IF"

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imported>Clippy
(Created page with ''''IF''' statements make Boolean True or False program evaluations to automate program decision making. <center>''Syntax:'' IF evaluation is true THEN execute code</center> *…')
 
imported>SMcNeill
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* With multiple code lines to run, end the IF statement with THEN and place all of the code on lines below that line.
 
* With multiple code lines to run, end the IF statement with THEN and place all of the code on lines below that line.
 
* With multiple code lines to run (a IF...END IF block), the IF statement and END IF statement must be the first statement on the line!
 
* With multiple code lines to run (a IF...END IF block), the IF statement and END IF statement must be the first statement on the line!
* Qbasic's IDE may return an error pointing somewhere else if you forget to use END IF!
+
* The [[IDE]] may point to an [[ERROR Codes|error]] in a loop or somewhere else if you forget to use END IF (typically a ''PROGRAM FLOW ERROR!'' message).
 
* Use colons to change multiple values in a one line IF statement. You cannot use AND on the other side of THEN!
 
* Use colons to change multiple values in a one line IF statement. You cannot use AND on the other side of THEN!
  

Revision as of 11:00, 2 September 2017

IF statements make Boolean True or False program evaluations to automate program decision making.


Syntax: IF evaluation is true THEN execute code
  • The evaluation by IF must be true for the THEN code to be run.
  • IF statements can also have alternative evaluations using ELSEIF and ELSE conditions.
  • When the IF statement and/or code to be run is more than code line, an END IF statement MUST be used.
  • With multiple code lines to run, end the IF statement with THEN and place all of the code on lines below that line.
  • With multiple code lines to run (a IF...END IF block), the IF statement and END IF statement must be the first statement on the line!
  • The IDE may point to an error in a loop or somewhere else if you forget to use END IF (typically a PROGRAM FLOW ERROR! message).
  • Use colons to change multiple values in a one line IF statement. You cannot use AND on the other side of THEN!


See also: IF...THEN



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