deleting specific value of array

Question

I have an array containing the numbers 1 to 10. When i select one random array key, i want to delete this one The following code does something like it, but just not good enough.

$imgArray = range(1,9);
$rand_key = array_rand($imgArray);
$imgValue = $imgArray[$rand_key];
unset($imgArray[$imgValue]);

The code deletes a value from the array, but it deletes the wrong one, Echoing the array gives the following result:

Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
    [4] => 5
    [5] => 6
    [6] => 7
    [7] => 8
    [8] => 9
)

Random selected item would be like number 4 but then it deletes array KEY 4, not array value 4..

Is there any way to change that? besides changing the variable(using -1)?

Vineet1982 · Accepted Answer · 2013-05-23 08:06:16Z

7

As such there is no way to delete the unset the value by function but the You pay the trick for simplest function? Well, you won't find anything simpler.

$array=array(312, 401, 1599, 3);
$toDelete=401;

$array=array_diff($array, array($toDelete));

answered May 23, 2013 at 8:06

Vineet1982

7,9285 gold badges34 silver badges70 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Jon · Accepted Answer · 2013-05-23 08:03:10Z

5

array_search will return the key for the value that you search for, if it finds it:

$rand_key = array_rand($imgArray);
$imgKey   = array_search($imgArray[$rand_key]);

if ($imgKey !== false) {
    unset($imgArray[$imgKey]);
}

Of course you don't really need to do this, because $rand_key is already a key in the array (array_rand returns a key!) so the code reduces to:

$rand_key = array_rand($imgArray);
// optional, if you need the value for something:
// $rand_val = $imgArray[$rand_key];
unset($imgArray[$rand_key]);

answered May 23, 2013 at 8:03

Jon

439k85 gold badges756 silver badges820 bronze badges

4 Comments

SliQz Over a year ago

This didn't really solve my problem.. What i am trying to do(and maybe should have mentioned) is echo 9 images on a random base, without duplicates, so thats why i have to delete the exact values in the array. So when i echo img4.jpg i want key 3(value = 4) deleted from my array

Jon Over a year ago

@SliQz: Well, why don't you simply shuffle the array? After that you only need a bog-standard foreach.

SliQz Over a year ago

Well thats because im still in the testfase. In the end ill have 36 different images, and i only want to display 9, one of wich is already known

Jon Over a year ago

@SliQz: array_slice after shuffling to keep only 9. If you keep explaining anyone can keep finding appropriate solutions, you should have done this in the question itself.

ChristopheBrun · Accepted Answer · 2013-05-23 08:07:11Z

0

You are confusing keys and values, that's why. $imgArray is a range(1,9) but that's values. Your keys are range(0,8).

So *$rand_key* is actually not a random key but a random value.

Thus you delete the wrong... key and you're exposes to an OutOfBounds exception.

If you want to randomize searched values, the use array_search to retrieve and process the key

If you want to randomize searched keys, then use range(0,8).

answered May 23, 2013 at 8:07

ChristopheBrun

1,2077 silver badges22 bronze badges

2 Comments

Jon Over a year ago

"OutOfBounds" exception in PHP? Not likely.

ChristopheBrun Over a year ago

My bad. Index not found error, but you've got the point : still an error.

Nono · Accepted Answer · 2013-05-23 08:24:11Z

0

Try this:

// Create array
$imgArray = range(1,9);

// Get random key from array
$rand_key = array_rand($imgArray);

// Get key value from array
$imgValue = $imgArray[$rand_key];

// Delete value from array
unset($imgArray[array_search($imgValue,$imgArray)]);


Here is your array:
Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
    [4] => 5
    [5] => 6
    [6] => 7
    [7] => 8
    [8] => 9
)

rand_key: 2

imgValue: 3

After delete imgValue: 3

New Array
(
    [0] => 1
    [1] => 2
    [3] => 4
    [4] => 5
    [5] => 6
    [6] => 7
    [7] => 8
    [8] => 9
)

answered May 23, 2013 at 8:24

Nono

7,4024 gold badges42 silver badges41 bronze badges

Collectives™ on Stack Overflow

deleting specific value of array

4 Answers 4

Comments

4 Comments

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

4 Comments

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related