Test if one array is a subset of another

Question

How can I determine if one array is a subset of another (all elements in the first are present in the second)?

 $s1 = \"string1>string2>string3>string4&         


        

Answer 1

Simple: use array subtraction.

On array subtraction, you will know whether or not one array is a subset of the other.

Example:

if (!array_diff($array1, $array2)) {
    // $array1 is a subset of $array2
}

Reference: array_diff

You can use array_intersect also.