PHP is callable

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PHP : is_callable() function

Description

The is_callable() function is used to test that the contents of a variable, whether it can be called as a function or not.

Version

(PHP 4 and above)

Syntax

is_callable(var_name, syntax_only, callable_name)

Parameters

Name

Description

Required /
Optional

Type

var_name

Either the name of a function stored in a string variable, or an object and the name of a method within the object.

Required

Mixed*

syntax_only

If set to TRUE, the function only verifies if it is a function or a method. It rejects simple variables those are not strings and an array not having a valid structure.

Optional

Boolean

callable_name

Receives a "callable name". This option is implemented only for classes.

Optional

String

*Mixed : Mixed indicates that a parameter may accept multiple (but not necessarily all) types.

Return value

TRUE if var_name is callable, FALSE otherwise.

Value Type : Boolean.

Example :

  1. function foo(){  

  2. }  

  3. echo is_callable('foo');  

  4. echo is_callable('bar');  

  5. ?>  

Output :

1