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ReflectionClass::hasConstant

(PHP 5 >= 5.1.2, PHP 7, PHP 8)

ReflectionClass::hasConstant — 检查常量是否已经定义

说明

public ReflectionClass::hasConstant(string $name): bool

检查类中是否已经定义了指定的常量。

参数

name

要被检查的常量名称。

返回值

如果已定义返回 true，否则返回 false。

示例

示例 #1 ReflectionClass::hasConstant() 示例

<?php
class Foo {
const c1 = 1;
}

$class = new ReflectionClass("Foo");

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

以上示例的输出类似于：

bool(true)
bool(false)

参见