php array_search() function usage_PHP tutorial

Definition and usage

The array_search() function is the same as in_array(), searching for a key value in the array. If the value is found, the key of the matching element is returned. If not found, returns false.

Prior to PHP 4.2.0, functions returned null instead of false on failure.

If the third parameter strict is specified as true, the key name of the corresponding element will only be returned if the data type and value are consistent.

Grammar

array_search(value,array,strict)

Parameters

Description

value

Required. Specifies the value to search for in the array.

array

Required. The array to be searched.

strict

参数	描述
value	必需。规定在数组中搜索的值。
array	必需。被搜索的数组。
strict	可选。可能的值： true false - 默认 如果值设置为 true，还将在数组中检查给定值的类型。（参见例子 2）

Optional. Possible values:

• true
• false - default

If the value is set to true, the type of the given value will also be checked in the array. (See Example 2)

Example #1 array_search() ExampleCopy code

The code is as follows:


$array = array(0 => 'blue', 1 => 'red', 2 => 'green ', 3 => 'red');

$key = array_search('green', $array); // $key = 2;

$key = array_search('red', $ array); // $key = 1;
?>



Warning
This function may return the Boolean value FALSE, but it may also return a value equal to FALSE Non-Boolean value, such as 0 or "". See the Boolean Types chapter for more information. The === operator should be used to test the return value of this function.

Example 1

Copy code

The code is as follows:


$a=array("a"=>"Dog","b"=>"Cat","c"=>"Horse");

echo array_search("Dog",$a);
?>


Output: a

Example 2

Copy code

The code is as follows:


$a=array("a"=>"5","b"=>5,"c"=>"5");

echo array_search(5,$a,true);
?>

Output:

b http://www.bkjia.com/PHPjc/321549.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/321549.htmlTechArticle

Definition and usage The array_search() function is the same as in_array(), searching for a key value in the array. If the value is found, the key of the matching element is returned. If not found, return...