Uniqid () Description

Uniqid

Generate only one value.

Syntax:String uniqid (string prefix );

Return Value: String

Function Type: Encoding

 

Description

This function generates a unique string based on the current millisecond and specified prefix string. The prefix parameter is a prefix string that can contain up to 114 characters.

 

Example

In this example, a 32-character unique string is generated.

<? PHP
$ Token = MD5 (uniqid (RAND ()));
Echo $ token;
?>

 

Read the instruction about uniqid in the manual today:
Uniqid () returns a prefixed unique identifier based on the current time in microseconds.
Literal Translation:
Uniqid () returns a unique identifier with a prefix based on the current time accurate to microseconds.
It is based on the current time, but it does not explain the relationship with the current time.
Echo uniqid (); we can see that uniqid is always a hexadecimal number with a continuously changing length of 13.
<? PHP
Echo hexdec (uniqid ()/(Time () + microtime ());
?>
The output is about 1048576.
It can be concluded that uniqid is obtained after the current time is accurate to microsecond and then multiplied by 1048576 (20 power of 2) and finally converted to hexadecimal.
Uniqid can be used more widely after you know the relationship between uniqid and time. For example, uniqid can be used as the file name of a post in a text forum.
In the post index, you can easily search for a post by time.