ON...GOTO
Revision as of 13:09, 16 October 2017 by imported>SMcNeill (info on qbasic/quickbasic differences)
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
