... and as nobody mentioned it so far, if you just match against a literal string like 'hello', then you could also use the index function: 
# if 'hello' not contained in $string
if ( index($string, 'hello' ) == -1) { 
  # do something
}

[download]

-- Hofmator

In reply to Re: string does not contain by Hofmator
in thread string does not contain by Anonymous Monk

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