What is the function of the array_search function in PHP?

The array_search function is used to search for a given value in an array and return the corresponding key. It can be utilized to find the position of a specific value in an array.

The syntax of array_search is as follows:
array_search($value, $array, $strict)

In this case, $value represents the value to search for, $array is the array to search in, and $strict indicates whether to do a strict type comparison.

The array_search function will return the corresponding key if the value is found, or false if the value is not found.

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$array = array('a', 'b', 'c', 'd');
$key = array_search('c', $array); // 返回2
$key = array_search('e', $array); // 返回false
$key = array_search('b', $array, true); // 返回1（进行强类型比较）

It is important to be cautious when using the array_search function with large arrays as it may impact performance.