Convert string to unique numeric value in php

I needed a unique internal int to use that would represent several random content types that I couldn't hard code as class constants or config options. Yet I didn't want to refer to "2" when I could use the easier to follow term "post". So though up the a way to get a INT value from a string which seems to work fairly collision free for a couple items. Is there a way to do this in php rather than what I built? ``` $strings = array('post', 'comment', 'blog', 'article', 'forum', 'news', 'page'); foreach( $strings as $string ) { print $string . ' = '; $string = str_split($string); $sum = 0; foreach( $string as $char ) { $sum += ord($char); } var_dump( $sum ); print '<br />'; } ``` This has nothing to do with user input so don't worry about the obvious flaws in the design. :EDIT: I need a numeric index for storing in a database for fast look ups. i.e. to tell "posts" from "articles" or "news". Yet I don't know what those 1-8 types of content will be called so I can't hard code those as constants in the app. Therefore, the best thing I could figure would be to create a numeric version of each word (which means checking to make sure two words don't sum up to the same number). If this were for a system that would have more than 8 words then this method is doomed to failure do to the high probability of sum collisions. Also, if I had a choice in knowing what words would be used then this would also be terrible design as class constants would work much better.