我有一个类的常量如下：
class AClass
{
const CODE_NAME_123 = "value1";
const CODE_NAME_456 = "value2";
}
有没有办法将AClass::CODE_NAME_123等常量的名称转换为字符串，例如从字符串中提取尾部数字？
您可以使用这样的东西：
//PHP's ReflectionClass will allow us to get the details of a particular class
$r = new ReflectionClass('AClass');
$constants = $r->getConstants();
//all constants are now stored in an array called $constants
var_dump($constants);
//example showing how to get trailing digits from constant names
$digits = array();
foreach($constants as $constantName => $constantValue){
$exploded = explode("_", $constantName);
$digits[] = $exploded[2];
}
var_dump($digits);
您可以使用ReflectionClass::getConstants()并迭代结果以找到具有特定值的常量，然后使用regex:从常量名称中获取最后一位数字
<?php
class AClass
{
const CODE_NAME_123 = "foo";
const CODE_NAME_456 = "bar";
}
function findConstantWithValue($class, $searchValue) {
$reflectionClass = new ReflectionClass($class);
foreach ($reflectionClass->getConstants() as $constant => $value) {
if ($value === $searchValue) {
return $constant;
}
}
return null;
}
function findConstantDigitsWithValue($class, $searchValue) {
$constant = findConstantWithValue($class, $searchValue);
if ($constant !== null && preg_match('/'d+$/', $constant, $matches)) {
return $matches[0];
}
return null;
}
var_dump( findConstantDigitsWithValue('AClass', 'foo') ); //string(3) "123"
var_dump( findConstantDigitsWithValue('AClass', 'bar') ); //string(3) "456"
var_dump( findConstantDigitsWithValue('AClass', 'nop') ); //NULL
?>
DEMO
使用ReflectionClass()并循环遍历对每个值应用preg_match的结果键，以提取字符串的最后3个数字：
class AClass
{
const CODE_NAME_123 = "";
const CODE_NAME_456 = "";
}
$constants = new ReflectionClass('AClass');
$constants_array = $constants->getConstants();
foreach ($constants_array as $constant_key => $constant_value) {
preg_match('/'d{3}$/i', $constant_key, $matches);
echo '<pre>';
print_r($matches);
echo '</pre>';
}
输出为：
Array
(
[0] => 123
)
Array
(
[0] => 456
)