ON...GOSUB

• Source: https://www.freebasic.net/wiki/wikka.php?wakka=KeyPgOngosub
• Last revised: 2020-08-13

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Calls a label based on an expression

Syntax

` On expression Gosub label1[, ...]

`

Description

Branches to different labels depending on the value of expression. An expression value of 1 will branch to the first label, a value of 2 to the second, etc. If the value of expression is zero (0) or greater than the number of items in the list, execution continues on the next statement following the On...Gosub.

This statement behaves exactly like Gosub and execution may return to the statement following the On...Gosub using Return.

It is recommended that the structured Select Case conditional statement be used instead of On...Gosub.

Examples

start GeSHi

'' Compile with -lang qb

'$lang: "qb"

choice = 3
On choice GoSub labela, labelb, labelc
Print "Good bye."
End

labela:
Print "choice a"
Return

labelb:
Print "choice b"
Return

labelc:
Print "choice c"
Return

end GeSHi

Dialect Differences

• Only available in the -lang qb and -lang fblite dialects.
• On Gosub support is disabled by default in the -lang fblite unless the Option Gosub statement is used.

Differences from QB

• FreeBASIC does not generate a run-time error if expression is negative or greater than 255.

See also

• Select Case
• On...Goto
• Gosub
• Return (from Gosub)
• Option Gosub
• Labels

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