为每次点击生成一个唯一的ID [重复]

Question

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• PHP function to generate v4 UUID 13 answers

Suppose many users uploading their pics at one time. So how could i generate a unique id for every pic which could never match with other generated id.

$uniqId = time().'_'.rand();

or should is use.

uniqid();

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Answer 1

Using the uniqid() PHP function will probably be your best method, since no DB is used for files sent.

As per the PHP manual: uniqid — Generate a unique ID.

"Can be useful, for instance, if you generate identifiers simultaneously on several hosts that might happen to generate the identifier at the same microsecond."

Quoted from the PHP manual.

• http://php.net/manual/en/function.uniqid.php