ZendX stands for “Zend Framework – Extras Library"
ZendX was created with the intention of improving and building upon the already solid Zend Framework. They were introduced since Zend Framework version 1.7. Whilst the Zend Framework contains many great features, a need was felt to extend upon it's functionality. Rather than mix and match frameworks a repository of useful classes was created that built upon existing Zend Framework functionality.
The most notable additions to the library at present are the porting of the Java collections framework across to PHP and a RESTful style PHP web services implementation reminiscent of .NET web services.
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