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# rand

(PHP 3, PHP 4 , PHP 5)

rand -- Generate a random integer

## Description

int rand ( [int min, int max])

If called without the optional min, max arguments rand() returns a pseudo-random integer between 0 and `RAND_MAX`. If you want a random number between 5 and 15 (inclusive), for example, use rand (5, 15).

示範 1.rand() example

`<?php echo rand() . "\n"; echo rand() . "\n"; echo rand(5, 15); ?>`

The above example will output something similar to:

    7771
    22264
    11

> 備注: On some platforms (such as Windows) `RAND_MAX` is only 32768. If you require a range larger than 32768, specifying min and max will allow you to create a range larger than RAND_MAX, or consider using mt_rand() instead.

> 備注:由PHP 4.2.0 始，您不需要再使用 srand() 或 mt_srand() 為亂數產生器提供種子，因為這已自動的提供了。

> 備注: In versions before 3.0.7 the meaning of max was range. To get the same results in these versions the short example should be rand (5, 11) to get a random number between 5 and 15.

See also: srand(), getrandmax(), and mt_rand().

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