?? Syntax: If the variable exists and the value is not NULL, it will return its own value, otherwise it will return its The second operand.
//php7以前 if判断
if(empty($_GET['param'])) {
$param = 1;
}else{
$param = $_GET['param'];
}
//php7以前 三元运算符
$param = empty($_GET['param']) ? 1 : $_GET['param'];
//PHP7 null合并运算符
$param = $_GET['param'] ?? 1;//1//php7以前
define("CONTENT", "hello world");
echo CONTENT;//hello world
//PHP7
define('ANIMALS', [
'dog',
'cat',
'bird'
]);
echo ANIMALS[2];//bird
//PHP7 类外也可使用const来定义常量
const CONSTANT = 'Hello World';
echo CONSTANT;//Hello WorldThe combined comparison operator is used to compare two expressions. When b, it returns -1, 0 or 1 respectively. The principle of comparison is to follow the regular comparison rules of PHP.
//整数 echo 1 <=> 1; // 0 echo 1 <=> 2; // -1 echo 2 <=> 1; // 1 //浮点数 echo 1.5 <=> 1.5; // 0 echo 1.5 <=> 2.5; // -1 echo 2.5 <=> 1.5; // 1 //字符串 echo "a" <=> "a"; // 0 echo "a" <=> "b"; // -1 echo "b" <=> "a"; // 1
Two modes: mandatory (default) and strict mode. The following type parameters can be used: string, int, float, bool
//... 操作符: 表示这是一个可变参数. php5.6及以上的版本可使用: 函数定义的时候变量前使用.
function intSum(int ...$ints){
return array_sum($ints);
}
var_dump(intSum(2,'3.5'));//5
//严格模式
//模式声明：declare(strict_types=1); 默认情况值为0，值为1代表为严格校验的模式
declare(strict_types=1);
function add(int $a,int $b){
return $a+$b;
}
var_dump(add(2,'3.5')); //Fatal error: Uncaught TypeError: Argument 2 passed to add() must be of the type integerAdd support for return type declaration. Similar to parameter type declaration. (For usage, add: type name after the function definition)
//有效的返回类型
declare(strict_types = 1);
function getInt(int $value): int {
return $value;
}
print(getInt(6));//6//无效返回类型
declare(strict_types = 1);
function getNoInt(int $value): int {
return $value+'2.5';
}
print(getNoInt(6));//Fatal error: Uncaught TypeError: Return value of getNoInt() must be of the type integerAllows new class {} to create an anonymous object.
<?php
//php7以前 接口实现
interface User{
public function getDiscount();
}
class VipUser implements User{
//折扣系数
private $discount = 0.6;
public function getDiscount() {
return $this->discount;
}
}
class Goods{
private $price = 200;
private $objectVipUser;
//User接口VipUser类实现
public function getUserData(User $User){
$this->objectVipUser = $User;
$discount = $this->objectVipUser->getDiscount();
echo "商品价格:".$this->price*$discount;
}
}
$display = new Goods();
//常规实例化接口实现对象
$display->getUserData(new VipUser);//商品价格:120<?php
//php7 创建一个匿名的对象
interface User{
public function getDiscount();
}
class Goods{
private $price = 200;
private $objectVipUser;
public function getUserData($User){
$this->objectVipUser = $User;
$discount = $this->objectVipUser->getDiscount();
echo "商品价格:".$this->price*$discount;
}
}
$display = new Goods();
//new匿名对象实现user接口
$display->getUserData(new class implements User{
private $discount = 0.6;
public function getDiscount() {
return $this->discount;
}
});//商品价格:120The Closure::call() method was added as a short way to temporarily bind an object scope to a closure and call it. Its performance is faster compared to PHP5's bindTo. Much more.
<?php
//php7以前
class A {
private $attribute = 'hello world';
}
$getClosure = function(){
return $this->attribute;
};
$getAttribute = $getClosure->bindTo(new A, 'A');//中间层闭包
echo $getAttribute();//hello world<?php
//PHP7
class A {
private $attribute = 'hello world';
}
$getClosure = function(){
return $this->attribute;
};
echo $getClosure->call(new A);//hello worldunserialize() function: The filtering feature can prevent illegal data from being injected into the code, providing a safer response Serialized data
<?php
class A{
public $name = 'admin_a';
}
class B{
public $name = 'admin_b';
}
$objA = new A();
$objB = new B();
$serializedObjA = serialize($objA);
$serializedObjB = serialize($objB);
//默认行为是接收所有类; 第二个参数可以忽略
$dataA = unserialize($serializedObjA , ["allowed_classes" => true]);
var_dump($dataA);//object(A)#3 (1) { ["name"]=> string(7) "admin_a" }
//如果allowed_classes设置为false,unserialize会将所有对象转换为__PHP_Incomplete_Class对象
$dataA = unserialize($serializedObjA , ["allowed_classes" => false]);
var_dump($dataA);//object(__PHP_Incomplete_Class)#4 (2) { ["__PHP_Incomplete_Class_Name"]=> string(1) "A" ["name"]=> string(7) "admin_a" }
//转换所有对象到 __PHP_Incomplete_Class对象，除了对象"B"
$dataB = unserialize($serializedObjB , ["allowed_classes" => ["B"]]);
var_dump($dataB);//object(B)#3 (1) { ["name"]=> string(7) "admin_b" }IntlChar: Provides access to some practical methods that can be used to access Unicode character information. Note: The Intl extension must be installed to use !
var_dump(IntlChar::CODEPOINT_MAX);//int(1114111) echo '<br>'; var_dump(IntlChar::charName('+'));//string(9) "PLUS SIGN" echo '<br>'; var_dump(IntlChar::ispunct('?'));//bool(true)
The CSPRNG function provides a simple mechanism to generate random numbers for passwords.
random_bytes() - A cryptographically protected pseudo-random string.
random_int() - A cryptographically protected pseudo-random integer.
$bytes = random_bytes(8); echo(bin2hex($bytes));//随机2073a110a2e3c497 echo '<br>'; echo(random_int(1, 999));//随机786 echo '<br>'; print(random_int(-999, -1));//随机-357
You can use a single use statement to import classes, functions and constants from the same namespace instead of using multiple use statements.
//PHP7之前
use some\namespace\ClassA;
use some\namespace\ClassB;
use some\namespace\ClassC as C;
use function some\namespace\fn_a;
use function some\namespace\fn_b;
use function some\namespace\fn_c;
use const some\namespace\ConstA;
use const some\namespace\ConstB;
use const some\namespace\ConstC;
// PHP7之后
use some\namespace\{ClassA, ClassB, ClassC as C};
use function some\namespace\{fn_a, fn_b, fn_c};
use const some\namespace\{ConstA, ConstB, ConstC};The newly added intdiv() function receives two parameters, and the return value is the value of the first parameter divided by the second parameter and rounded.
echo intdiv(8,4);//2 echo intdiv(10,4);//2 echo intdiv(5,10);//0
PHP7 has changed the way most errors are reported. Unlike PHP5’s traditional error reporting mechanism, most errors are now thrown as Error exceptions.
This Error exception can be treated like a normal exception Caught by a try/catch block. If there is no matching try/catch block, the exception handling function (registered by set_exception_handler()) is called for processing.
If the exception handling function has not been registered, it is processed in the traditional way : Reported as a fatal error (Fatal Error).
The Error class is not extended from the Exception class, so code such as catch (Exception $e) { ... } cannot catch Error . You can use code like catch (Error $e) { ... } or catch Error by registering an exception handling function (set_exception_handler()).
<?php
//php7以前 自定义异常处理
class getException extends Exception{
public function errorMsg(){
return '错误的信息'.$this->getMessage().'<br>错误的代码'.$this->getCode();
}
}
try {
$num =10;
if($num > 1) {
throw new getException($num,404);
}
} catch (getException $e) {
echo $e->errorMsg();
}<?php
//php7 异常处理
try {
test();
}catch(\Exception $e){
echo $e->getMessage();//自定义异常抛出
}catch(\Error $e) { //系统错误
echo $e->getMessage();//Call to undefined function test()
}
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