How to find out if a string is a serialized object/array or just a string?

Is there some reliable way to find out whether a string variable is just a string or a strin开发者_如何学Pythong representation of a serialized object/array?

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You can call unserialize(string $str) function: it returns false, if string cannot be unserialized.

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Well, you can tell by looking at the format. When you serialize an array, you get a string that looks like a:1:{i:0;s:3:"foo"} And if you serialize an object, you get: o:7:"myclass":1:{s:3:"foo";s:3:"bar";}.

So if you want to test rudimentary, you can do these two regexes:

^a:\d+:{.*?}$

And

^o:\d+:"[a-z0-9_]+":\d+:{.*?}$

for arrays and objects respectively.

Note that this just checks for the generic form. To tell if it's a valid serialized string, you need to run it through unserialize() and test the return is_array($result) and is_object($result)...