note 38220 added to function.substr

From: Date: Fri, 12 Dec 2003 17:11:39 +0000
Subject: note 38220 added to function.substr
Groups: php.notes 
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Just to clarify the meaning of the statement "If string is less than start characters long, FALSE will be returned. " If string length is exactly equal to startpos, then false is returned (not a zero-length string). Example: substr("filename.txt",9,1)==='.txt' but substr("filename.",9,1)!=='.' (it equals false) People often use this function to find a file extension (combined with strrpos). But, in the special case where the dot (.) you have to have code to handle that case in a way you want. People familiar with the "c" function of the same name, would have expected a zero-length string. Also, keep in mind that in the above example the use of *exact* comparison. You can only detect the difference between a zero-length string and false, if you use exact comparison (===). The two appear "equal" if you use approx match (==). As a result, this issue will not be immediately apparent. ---- Manual Page -- http://www.php.net/manual/en/function.substr.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+38220 Delete -- http://master.php.net/manage/user-notes.php?action=delete+38220&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+38220&report=yes Search -- http://master.php.net/manage/user-notes.php

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