Php/docs/reflectionparameter.getdefaultvalueconstantname

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ReflectionParameter::getDefaultValueConstantName

(PHP 5 >= 5.4.6, PHP 7)

ReflectionParameter::getDefaultValueConstantNameReturns the default value's constant name if default value is constant or null


说明

public ReflectionParameter::getDefaultValueConstantName ( ) : string

Returns the default value's constant name of the parameter of any user-defined or internal function or method, if default value is constant or null. If the parameter is not optional a ReflectionException will be thrown.


参数

此函数没有参数。


返回值

Returns string on success or null on failure.


更新日志

版本 说明
8.0.0 This method now allows getting the default values' constant names of built-in functions and

built-in class methods. Previously, a ReflectionException was thrown.


范例

Example #1 Getting default values' constant names of function parameters

<?phpfunction foo($test, $bar = PHP_INT_MIN){    echo $test . $bar;}$function = new ReflectionFunction('foo');foreach ($function->getParameters() as $param) {    echo 'Name: ' . $param->getName() . PHP_EOL;    if ($param->isOptional()) {        echo 'Default value: ' . $param->getDefaultValueConstantName() . PHP_EOL;    }    echo PHP_EOL;}?>

以上例程会输出:


Name: test

Name: bar
Default value: PHP_INT_MIN

参见