[PHP 4, PHP 5, PHP 7, PHP 8]
is_array — Finds whether a variable is an array
Description
is_array[mixed $value]: bool
Parameters
valueThe variable being evaluated.
Return Values
Returns true if value is an array, false otherwise.
Examples
Example #1 Check that variable is an array
The above example will output:
See Also
- array_is_list[] - Checks whether a given array is a list
- is_float[] - Finds whether the type of a variable is float
- is_int[] - Find whether the type of a variable is integer
- is_string[] - Find whether the type of a variable is string
- is_object[] - Finds whether a variable is an object
Rob Thomas ¶
5 years ago
Please note that the 'cast to array' check is horrendously out of date.
Running that code against PHP 5.6 results in this:
is_array : 0.93975400924683
cast, === : 1.2425191402435
So, please use 'is_array', not the horrible casting hack.
ari at umbrella dot bz ¶
6 years ago
hperrin's results have indeed changed in PHP 7. The opposite is now true, is_array is faster than comparison:
is_array : 0.52148389816284
cast, === : 0.84179711341858
Tested 1000000 iterations.
skaimauve at yahoo dot ca ¶
13 years ago
Or you could make use of the array_diff_key and array_key function:
In my tests it runs about twice as fast as Michael/Gabriel's array_reduce[] method.
[Speaking of which: Gabriel's version doesn't work as written; it reports associative arrays as numeric if only the first key is non-numeric, or if the keys are numeric but ordered backwards. Michael solves this problem by comparing array_reduce[] to count[], but that costs another function call; it also works to just compare to -1 instead of 0, and therefore return -1 as the ternary else from the callback].
hperrin at gmail dot com ¶
12 years ago
I've found a faster way of determining an array. If you use is_array[] millions of times, you will notice a *huge* difference. On my machine, this method takes about 1/4 the time of using is_array[].
Cast the value to an array, then check [using ===] if it is identical to the original.
You can use this script to test the speed of both methods.
What's faster for determining arrays?