In PHP, you can use the array_key_exists() function to determine whether the specified value is an array key. This function can check whether the specified key exists in an array; the syntax is "array_key_exists(key,array)" .
The operating environment of this tutorial: windows7 system, PHP7.1 version, DELL G3 computer
In php, you can use the array_key_exists() function To determine whether the specified value is an array key.
array_key_exists() function checks whether the specified key exists in an array. If the key exists, it returns true. If the key does not exist, it returns false.
Syntax:
array_key_exists(key,array)
key Required. Specifies the key name.
array Required. Specifies an array.
Example: Determine whether the specified value Volvo is an array key name
<?php header("Content-type:text/html;charset=utf-8"); $a=array("Volvo"=>"XC90","BMW"=>"X5"); if (array_key_exists("Volvo",$a)) { echo "指定值Volvo 是数组键名"; } else { echo "指定值Volvo 不是数组键名"; } ?>
Output result:
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