如何使用php获取STRING查询字符串值

Suppose if I have string like this:

rajeshpatel&rid=10&sid=20&mid=30

Then how can I get value of "rid" using php.

any help?

You can use parse_str as

$str = 'rajeshpatel&rid=10&sid=20&mid=30';
parse_str($str,$result);
print_r($result);
echo $result['rid'];//10

Or you can use it in another way as

parse_str($str);
echo $rid;//10

Fiddle