Name

FILTER — Strips string of illegal characters

Synopsis

FILTER(allowed-chars|string)

Filters the string to include only the characters shown in allowed-chars:

; Ensure that the Caller*ID number contains only digits
exten => Set(CALLERID(num)=${FILTER(0123456789,${CALLERID(num)})})

This function may only be read, not set.

See Also

QUOTE()

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