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53 lines
1.2 KiB
Markdown
53 lines
1.2 KiB
Markdown
[ON...GOTO](ON...GOTO) is a control-flow statement that branches to a line or label in a list depending on a numerical expression.
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## Syntax
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> **ON** numericalExpression [GOTO](GOTO) labelOrNumber[,labelOrNumber][,...]
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## Description
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* 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.
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* The procedure must be used after the number value is determined or in a loop to monitor current user events.
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* **Note:** [SELECT CASE](SELECT-CASE) provides a much more convenient way of doing this task.
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## QBasic
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* In QuickBASIC 4.5 the list could contain a maximum of 60 line numbers or labels, while **QB64** has no limit.
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## Example(s)
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Changing the program flow when a value is not 0.
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```vb
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CLS
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a = 2
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ON a GOTO hello, hereweare, 143
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END
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hello:
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PRINT "you don't get to see this!"
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END
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hereweare:
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PRINT "And here we are..."
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END
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143
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PRINT "you don't get to see this neither..."
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END
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```
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```text
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And here we are...
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```
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*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.
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## See Also
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* [ON...GOSUB](ON...GOSUB)
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* [GOTO](GOTO)
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* [GOSUB](GOSUB)
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* [SELECT CASE](SELECT-CASE)
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