A simple example of randomly selecting values ​​from a php array

This article mainly introduces simple examples of random values ​​​​for PHP arrays. It has certain reference value. Now I share it with everyone. Friends in need can refer to

array_rand() when you want to start from Very useful when removing one or more random cells from an array. It accepts input as an input array and an optional parameter num_req, specifying how many cells you want to remove - if not specified, it defaults to 1.

array_rand -- Randomly remove one or more cells from an array

mixed array_rand ( array input [, int num_req])

array_rand() is useful when you want to remove one or more random cells from an array. It accepts input as an input array and an optional parameter num_req, specifying how many cells you want to remove - if not specified, it defaults to 1.
If you only take out one, array_rand() returns the key name of a random unit, otherwise it returns an array containing random key names. This way you can randomly pull out keys and values ​​from the array.
Don’t forget to call srand() to seed the random number generator.

Example 1. array_rand() Example

srand ((float) microtime() * 10000000);  
$input = array ("Neo", "Morpheus", "Trinity", "Cypher", "Tank");  
$rand_keys = array_rand ($input, 2);  
print $input[$rand_keys[0]]."\n";  
print $input[$rand_keys[1]]."\n";

We have visited such a website, and every time the banner is refreshed, it is random. Changes, in this article, we will introduce to you how to use PHP to implement this function.

Steps

The principle of program implementation is: call an array, each image corresponds to an element in the array, and then we set a random number. As long as a piece of data is randomly obtained, an image can be displayed. image.

The first step is for us to generate a random number. We get different random numbers every time we refresh. The specific code is:

srand((float) microtime() * 10000000);

After that, we set an array as image, and then set 5 array elements. The code is as follows:

$image[1]='/location/of/image1.jpg';  
$image[2]='/location/of/image2.jpg';  
$image[3]='/location/of/image3.jpg';  
$image[4]='/location/of/image4.jpg';  
$image[5]='/location/of/image5.jpg';

The following code implements the function of randomly selecting an element from the array:

$rn = array_rand($image);

Then we display a random picture:

echo &#39;<img src="&#39;.$image[$rn].&#39;">&#39;;

Combine the above codes. That's it.

srand((float) microtime() * 10000000);  
$image[1]='/location/of/image1.jpg';  
$image[2]='/location/of/image2.jpg';  
$image[3]='/location/of/image3.jpg';  
$image[4]='/location/of/image4.jpg';  
$image[5]='/location/of/image5.jpg';  
$rn = array_rand($image);  
echo &#39;<img src="&#39;.$image[$rn].&#39;">&#39;;

The above code is our code for randomly displaying pictures. If we want to add each picture with its own connection address, then we can slightly change the above code! Change the above array to a two-dimensional array:

$image[1]['pic']='/location/of/image1.jpg';  
$image[1]['link']='/location/of/link1.php';

The corresponding display code is:

echo &#39;<a href="&#39;.$image[$rn][&#39;link&#39;].&#39;">&#39;;  
echo &#39;<img src="&#39;.$image[$rn][&#39;pic&#39;].&#39;">&#39;;

Then we can complete the function of our title, randomly display pictures and connect to different specified Address:

srand((float) microtime() * 10000000);  
$image[1]['pic']='/location/of/image1.jpg';  
$image[1]['link']='/location/of/link1.php';  
$image[2]['pic']='/location/of/image2.jpg';  
$image[2]['link']='/location/of/link2.php';  
$image[3]['pic']='/location/of/image3.jpg';  
$image[3]['link']='/location/of/link3.php';  
$image[4]['pic']='/location/of/image4.jpg';  
$image[4]['link']='/location/of/link4.php';  
$image[5]['pic']='/location/of/image5.jpg';  
$image[5]['link']='/location/of/link5.php';  
$rn = array_rand($image);  
echo &#39;<a href="&#39;.$image[$rn][&#39;link&#39;].&#39;">&#39;;  
echo &#39;<img src="&#39;.$image[$rn][&#39;pic&#39;].&#39;">&#39;;

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