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Double Dollars in PHP
What does this print?
<?php $first = "fur"; $last = "feather"; $$first = "yum yum "; ${"$first$last"} = "yikes"; print "$fur $furfeather"; ?> It prints "yum yum yikes". In PHP, you can write a variable name within a variable name, and that's what I've done in this example. The variable called "first" is set to contain the word "fur" The variable who's name is in first - so that's the variable called fur - is set to "yum yum" The variable called "last" is set to "feather" The variable who's name is made up of the string in the variable first followed by the string in the varaible last - so that's the variable called furfeather - is set to "yikes". This is a facility to be used sparingly - it's quite easy to write code that's unmaintainable using such structures, though they can be very useful at times for helping to generalise code. (written 2005-11-02 23:17:57) Associated topics are indexed under H999 - Additional PHP MaterialH103 - PHP - Variables, Operators and Expressions
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On line course booking - credit card protectionRail services under threat - Swindon, Melksham ... and Newquay and Bicester too North, Norther and Northest - PHP 5 Objects Setting the file name for a downloaded document Double Dollars in PHP Different ways of selling PHP upgrade - traps to watch New look to website New servlet from old Watch what you wear 1635 posts, page by page
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