Searches the array for a given value and returns the first corresponding key if successful (original) (raw)

array_search

(PHP 4 >= 4.0.5, PHP 5, PHP 7)

array_search — Searches the array for a given value and returns the first corresponding key if successful

Description

array_search ( mixed $needle , array $haystack [, bool $strict = FALSE ] ) : mixed

Parameters

needle

The searched value.

Note:

If needle is a string, the comparison is done in a case-sensitive manner.

haystack

The array.

strict

If the third parameter strict is set to TRUE then the array_search() function will search for_identical_ elements in thehaystack. This means it will also perform astrict type comparison of theneedle in the haystack, and objects must be the same instance.

Return Values

Returns the key for needle if it is found in the array, FALSE otherwise.

If needle is found in haystack more than once, the first matching key is returned. To return the keys for all matching values, use array_keys() with the optionalsearch_value parameter instead.

Warning

This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE. Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

Changelog

Version	Description
5.3.0	As with all internal PHP functions as of 5.3.0,array_search() returns NULL if invalid parameters are passed to it.

Examples

Example #1 array_search() example

<?php <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>a</mi><mi>r</mi><mi>r</mi><mi>a</mi><mi>y</mi><mo>=</mo><mi>a</mi><mi>r</mi><mi>r</mi><mi>a</mi><mi>y</mi><mo stretchy="false">(</mo><mn>0</mn><mo>=</mo><msup><mo>></mo><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mi>b</mi><mi>l</mi><mi>u</mi><msup><mi>e</mi><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mo separator="true">,</mo><mn>1</mn><mo>=</mo><msup><mo>></mo><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mi>r</mi><mi>e</mi><msup><mi>d</mi><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mo separator="true">,</mo><mn>2</mn><mo>=</mo><msup><mo>></mo><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mi>g</mi><mi>r</mi><mi>e</mi><mi>e</mi><msup><mi>n</mi><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mo separator="true">,</mo><mn>3</mn><mo>=</mo><msup><mo>></mo><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mi>r</mi><mi>e</mi><msup><mi>d</mi><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mo stretchy="false">)</mo><mo separator="true">;</mo></mrow><annotation encoding="application/x-tex">array = array(0 => 'blue', 1 => 'red', 2 => 'green', 3 => 'red');</annotation></semantics></math>array=array(0=>′blue′,1=>′red′,2=>′green′,3=>′red′);key = array_search('green', <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>a</mi><mi>r</mi><mi>r</mi><mi>a</mi><mi>y</mi><mo stretchy="false">)</mo><mo separator="true">;</mo><mi mathvariant="normal">/</mi><mi mathvariant="normal">/</mi></mrow><annotation encoding="application/x-tex">array); // </annotation></semantics></math>array);//key = 2; <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>k</mi><mi>e</mi><mi>y</mi><mo>=</mo><mi>a</mi><mi>r</mi><mi>r</mi><mi>a</mi><msub><mi>y</mi><mi>s</mi></msub><mi>e</mi><mi>a</mi><mi>r</mi><mi>c</mi><mi>h</mi><msup><mo stretchy="false">(</mo><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mi>r</mi><mi>e</mi><msup><mi>d</mi><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">key = array_search('red', </annotation></semantics></math>key=arraysearch(′red′,array); // $key = 1; ?>