使用随机值PHP创建关联数组

Question

I am trying to generate an associate array with random values. For example, if I give you this string:

something, anotherThing, foo, bar, baz

(the length of the string is dynamic - so there could be 10 items, or 15);

I would like to create an array based on those values:

$random = rand();
array("something"=>$random, "anotherThing"=>$random, "foo"=>$random, "bar"=>$random, "baz"=>$random);

And it builds the array based on how many values it's given.

I know how to order them into an array like so:

explode(", ", $valueString);

But how can I assign the values to make it an associative array?

Thanks.

Answer 1

NOTE: I am assuming that you want each item to have a different random value (which is not exactly what happens in your example).

With PHP 5.3 or later, you can do this most easily like so:

$keys = array('something', 'anotherThing', 'foo', 'bar', 'baz');
$values = array_map(function() { return mt_rand(); }, $keys);

$result = array_combine($keys, $values);
print_r($result);

For earlier versions, or if you don't want to use array_map , you can do the same thing in a more down to earth but slightly more verbose manner:

$keys = array('something', 'anotherThing', 'foo', 'bar', 'baz');
$result = array();
foreach($keys as $key) {
    $result[$key] = mt_rand();
}

print_r($result);

Answer 2

all example are good, but not simple

1. Init array

    $arr = array(); 

2. How many values your need?

    $m = 10; 

3. save random to all elements of array

    for ($i=0;$i<$m;$i++) { $arr[$i] = mt_rand(); } 

Why make more complex this simple example?

, Arsen

Answer 3

I suppose you have the keys in $key_array. This will make $random the value of each key:

$random = rand();
$array = array_fill_keys($key_array, $random);

If you need a way to apply different random values to each element, here's one (of several) solutions:

$array = array_fill_keys($key_array, 0);
foreach($array as &$a) {
  $a = rand();
}