Appending Arrays

[moldboy 0]

When you have a normal variable say $string and you want to add more to it you would use the .= construct, but how does one go about doing that with an array, I have an IF structure that determins what options the user has selected, so I have something like:

$array = NULL;IF (isset($_POST['op1])){$array .= array(1, 2, 3, 4);}IF (isset($_POST['op2'])){$array .= array(5, 6, 7, 8);}

So if there is a value for op1 then the array contains 1,2,3,4 is there is a value for op2 then the array contains 5,6,7,8 and if both are set the array contains 1,2,3,4,5,6,7,8, or atleaset that's the plan, you see if I try to preform any array specific functions like random select, it tells me that the first entry is required to be an array, or something like that, so how can I create an array and then add more to it?

[truefusion 3]

Try this:

<?$array = array(1, 2, 3, 4, 5, 6, 7, 8);IF (isset($_POST['op1])){$array = array_slice($array, 0, 4);}IF (isset($_POST['op2'])){$array = array_slice($array, 4, 4);}IF (isset($_POST['op3'])){$array}?>

I haven't tested it, but i'm sure it'll work to your purpose. Modify where needed.

[Spectre 0]

PHP has very easy to use array handling - much easier than most other programming languages I know of (take C, for instance).

 

An array is created with the array() function, as you are obviously already aware. The array_merge() function allows you to merge one array with another. You could probably use this to get around your problem:

 

$array = array();if( isset($_POST['op1']) ) {  $array = array(1,2,3,4);}if( isset($_POST['op2']) ) {  $array = array_merge($array,array(5,6,7,8));}

This would mean that if the POST variable 'op1' is set, then the array would be assigned the value of { 1,2,3,4 } - and if 'op2' is set, then the current array will be merged with an array consisting of { 5,6,7,8 } (and if only 'op2' is set, the array will only equal { 5,6,7,8 }).

 

There are a lot of different ways to fiddle with arrays in PHP. This is just one example.

 

Hope it helps.

[moldboy 0]

I'd love to say that worked but it appears to still think the variable isn't an array.

[Spectre 0]

Did you try the method I mentioned? You can't use '.' (a full stop) to append to an array, only to a string.In the code I posted, $array is being initialized as an array - and then assigned the values of an array later. Meaning that it should be considered an array.Try using is_array($array); to determine if it is an array and use print_r($array); to recursively print the values in the array.