PHP rand() Function
Definition
The rand()
function returns random numbers. If you call it with no parameters, it will
return a number between 0 and the value returned by getrandmax()
.
Syntax
PHP rand() Function has the following syntax.
int rand ( [int min, int max] )
Parameter
Parameter | Is Required | Description |
---|---|---|
min | Optional. | Lowest number to be returned. Default is 0 |
max | Optional. | Highest number to be returned. Default is getrandmax() |
If you supply it with two parameters, rand()
will use those numbers as the upper and
lower limits of the random number, inclusive of those values. That is, if you specify 1
and 3, the value could be 1, 2, or 3.
Return
Item | Value |
---|---|
Return Value | A random integer between min (or 0) and max (or getrandmax() inclusive) |
Return Type | Integer |
Note
If you want a random integer between 10 and 100 (inclusive), use rand (10,100). The mt_rand() function produces a better random value, and is 4 times faster than rand().
Example 1
<?PHP
$random = rand();
$randrange = rand(1,10);
?>
The numbers generated by rand()
are more
predictable than using the mt_rand()
function.
Example 2
Display Random picture
<html>//www.j ava 2 s . com
<body>
<?php
srand( microtime() * 1000000 );
$num = rand( 1, 4 );
switch( $num ){
case 1 : $car = "a.jpg"; $url="a.php"; break;
case 2 : $car = "f.jpg"; $url="f.php"; break;
case 3 : $car = "j.jpg"; $url = "j.php"; break;
case 4 : $car = "p.jpg"; $url = "p.php"; break;
}
$banner = "<a href='$url'>";
$banner.= "<img src='$car'";
$banner.= "width='380' height='110'>";
$banner.="</a>";
echo( $banner );
?>
</body>
</html>