ReflectionClass
PHP Manual

ReflectionClass::hasConstant

(PHP 5 >= 5.1.0)

ReflectionClass::hasConstant — Checks if constant is defined

说明

public bool ReflectionClass::hasConstant ( string $name )

Checks whether the class has a specific constant defined or not.

参数

name

The name of the constant being checked for.

返回值

TRUE if the constant is defined, otherwise FALSE.

范例

Example #1 ReflectionClass::hasConstant() example

<?php
class Foo {
    const c1 = 1;
}

$class = new ReflectionClass("Foo");

var_dump($class->hasConstant("c1"));
var_dump($class->hasConstant("c2"));
?>

以上例程的输出类似于：

bool(true)
bool(false)

参见

ReflectionClass
PHP Manual