search and replace value in PHP array

Question

I was looking for some standard PHP function to replace some value of an array with other, but surprisingly I haven\'t found any, so I have to write my own:

Answer 1

 $green_key = array_search('green', $input); // returns the first key whose value is 'green'

$input[$green_key] = 'apple'; // replace 'green' with 'apple'