PHP random text once - php

Question

I've been looking for the solution of my problem for ages and I still haven't found it so i desided to create a stackoverflow account to ask the question myself.
this is what I created so far:
<? //Chooses a random number $num = Rand (1,2);
switch ($num){
case 1: $retrieved_data = "test"; break;
case 2: $retrieved_data = "test1"; break;
} ?>
And this is the place where I want the text to appear;
<form enctype="multipart/form-data" action="upload.php" method="POST">
<input name="<?php echo $retrieved_data; ?>" type="file" />
<input name="<?php echo $retrieved_data; ?>" type="file" />
<input type="submit" value="Upload" /></form>
My problem is I want to have the "test1" and "test" randomly displayed on these places
but I want them to be different from eachother every time. So if the first input type is "test" I want the second input type to be 'test1" but I can't seem to get this working
Does anyone know what I'm doing wrong or a code to make this possible?

Answer 1

If you have limited number of possibilities, put them int an array, shuffle it and shift/pop elements from it:
$retrieved_data = array('test', 'test1');
shuffle($retrieved_data);
$random1 = array_shift($retrieved_data);
$random2 = array_shift($retrieved_data);

Answer 2

Step A - you are selecting a number, 1 or 2
Step B - you are running that number through your switch case, this case ONLY takes the number that it receives and assigns it a value. Therefore if your number is 1, your switch case ends at $retrieved_data = "test". If your number is 2 your switch case goes to case 2 and assigns $retrieved_data = "test 1".
Step C = $retrieved_data is assigned to your form (it will have only one value, "test" or "test1".

Answer 3

Use array_rand() for that.
$aName = array('test1', 'test2', 'whatever');
function getRandom(array &$aName)
{
if (($key = array_rand($aName)) === NULL) {
throw new Exception('No more randomness!');
}
$value = $aName[$key];
unset($aName[$key]);
return $value;
}
So simply use getRandom($aName) when you need a unique random item from the array.