RN笔记

语法

1.some test

let a = {o: "091"}
a['8'] = "90"
a[Symbol.iterator] = function* () {
    yield 1;
    yield 2;
    yield 3;
};
Object.getPrototypeOf(a).a = 898
let b = Object.create(a)
Object.getPrototypeOf(b).a = 666
let car = new Car("ma","mo","ye")
    //Object.getOwnPropertyNames(Object.getPrototypeOf(a))
console.log(Object.getOwnPropertyNames(Object.getPrototypeOf(car)));

function showProps(obj, objName) {
    var result = "";
    for (var i in obj) {
        if (obj.hasOwnProperty(i)) {
            result += objName + "." + i + " = " + obj[i] + "\n";
        }
    }
    return result;
}

function Car(make, model, year) {
    this.make = make;
    this.model = model;
    this.year = year;
}

function forProps(obj) {
    let object = obj;
    let resullt = ""
    do {
        object = Object.getPrototypeOf(object);
        resullt += object +"\n"
    } while (object);
    return resullt

}

function* fibonacci() {
    let a = 0, b = 1;
    while (true) {
        yield b;
        [a, b] = [b, a + b];
    }
}

3. function a() {
   }
   
   function B() {
       this.b = "12"
   }
   
   class C {
       e() {
       }
   }
   
   let d = {}
   console.log(B.__proto__ === Object.getPrototypeOf(B))
   // new B().__proto__ === Object.getPrototypeOf(new B()) 
   // B.prototype === Object.getPrototypeOf(new B())
   // B.prototype["constructor"] === B 
   // Object.getPrototypeOf(new B())["constructor"] === B 
   // B.__proto__  === Object.getPrototypeOf(B)  
   // B.__proto__  != B.prototype   // Object.getPrototypeOf(B) 为 function (){ [native code] } , 而 Object.getPrototypeOf(new B()) === B.prototype 为 {constructor:B}
   // 以上同样规则 使用a 与 C .只是C.prototype 为 {constructor:C,e:(){}},多了C的成员函数的变量。如果想让B与C达到一样，只需B.prototype.e = function (){}即可
   ````
   2.`...`eg: