It’s common knowledge you can read variable from a URL querystring by using $_GET array in PHP, but that’s only possible if the URL is “executed” in the browser.
For those who might not know, querystrings are those variable-value pairs that appears behind ‘?’ of a URL. For example,
http://www.mysite.com/index.php?variable1=1&variable2=1
gives the querystring “variable1=1&variable2=1″.
What happens if you end up reading a URL from, say, a text file and you want to parse the querystring? In this case, the $_GET won’t work. So instead, PHP provides a function called parse_str(), which will convert the querystring into actual PHP variables within the scope of the code.
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