ON...GOTO

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ON...GOTO is a control-flow statement that branches to a line or label in a list depending on a numerical expression.


Syntax

ON numericalExpression GOTO labelOrNumber[,labelOrNumber][,...]


Description

  • numericalExpression represents the line or label that the program should branch to: 1 branches to the first line or label in the list, 2 branches to the second, etc.
  • The procedure must be used after the number value is determined or in a loop to monitor current user events.
  • Note: SELECT CASE provides a much more convenient way of doing this task.


QBasic/QuickBASIC

  • In QuickBASIC 4.5 the list could contain a maximum of 60 line numbers or labels, while QB64 has no limit.


Examples

Example: Changing the program flow when a value is not 0.

CLS a = 2 ON a GOTO hello, hereweare, 143 END hello: PRINT "you don't get to see this!" END hereweare: PRINT "And here we are..." END 143 PRINT "you don't get to see this neither..." END

And here we are...

Explanation: Since a equals 2 it goes to the second item in the list (hereweare) and branches to there. Try changing a' to 1 or 3.


See also



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