How do I find out if a value is already in an array?
PHP provides a very useful function called in_array that lets you check whether a value is already in the array or not. Here is an example of it in use when we want to check if certain numbers are present in an array or not:
<?php
$numbers = range(1,10);
$checknumbers = array(1,20,10);
foreach($checknumbers as $isitthere) {
if(in_array($isitthere,$numbers)) { echo "The number $isitthere is in the numbers array\n\n"; }
else { echo "The number $isitthere is NOT in the numbers array\n\n"; }
}
?>
This prints:
The number 1 is in the numbers array
The number 20 is NOT in the numbers array
The number 10 is in the numbers array
More arrays PHP Questions
How do you remove duplicate values from an array?I want to invert my array, can I do this?
How do I check if a variable is of array type?
How do I reverse sort an array by key?
How do I add to the end of an array and know how large the array is?