PHP array_flip() is an inbuilt function that flips/exchanges all keys with their associated values in the array. The array_flip() function returns the array in flip order; for example, keys from array become values and values from array become keys. The values of the array need to be the valid keys, i.e., they need to be either an integer or string. A warning will be emitted if the value has the wrong type, and the key-value pair in question will not be included in the result.

PHP Array Flip Example

PHP array_flip() this function very useful when you have a big array, and you want to know if a given value is in the array.

The  in_array() becomes quite slow in such a case, but you can flip the big array and then use the  isset() function to obtain the same result in a much faster way.

#php #php array flip