[PHP] laravel data_get函数以及?? ?: 测试用例

        $arr=[
            "name"=>"陶士涵",
            "title"=>[
                "sub"=>"测试"
            ],
            "test"=>null,
            "desc"=>"",
            "num"=>0,
        ];

        $name=data_get($arr,"name","a");
        $subTitle=data_get($arr,"title.sub","a");
        $mainTitle=data_get($arr,"title.main","a");//如果没有这个key的情况下，默认值起作用,返回string(1) "a"
        $test=data_get($arr,"test","a");//如果是null的情况下，默认值不起作用,返回null
        $test2=data_get($arr,"test","a") ?? "a";//如果是null的情况下，??可以起作用,返回string(1) "a"
        $desc=data_get($arr,"desc","a") ?: "a";//如果是""的情况下，?:可以起作用,返回string(1) "a"
        $num=data_get($arr,"num","a") ?: 100;//如果是0的情况下，?:可以起作用,返回int(100)
        var_dump($name,$subTitle,$mainTitle,$test,$test2,$desc,$num);