typeof /s/ === 'object'; // Chrome 12+ , 符合 ECMAScript 5.1 typeof /s/ === 'object'; // Firefox 5+ , 符合 ECMAScript 5.1 // 函数 typeof function(){} === 'function'; typeof Math.sin === 'function'; typeof /s/ === 'function'; // Chrome 1-12 , 不符合 ECMAScript...
o2instanceofC;// trueoinstanceofC;// false, because C.prototype is nowhere in o's prototype chain anymoreD.prototype=newC();// use inheritancevaro3 =newD(); o3instanceofD;// trueo3instanceofC;// true varmyString =newString();varmyDate =newDate(); myStringinstanceofString;// return...
//Numberstypeof37 === 'number';typeof3.14 === 'number';typeofMath.LN2 === 'number';typeofInfinity === 'number';typeofNaN === 'number';//尽管NaN是"Not-A-Number"的缩写,意思是"不是一个数字"typeofNumber(1) === 'number';//不要这样使用!//Stringstypeof"" === 'string';typeo...
D.prototype = new C(); // use inheritance var o3 = new D(); o3 instanceof D; // true o3 instanceof C; // true var myString = new String(); var myDate = new Date(); myString instanceof String; // returns true myString instanceof Object; // returns true myString instanceof...
Type又叫类型别名(type alias),作用是给一个类型起一个新名字,不仅支持interface定义的对象结构,还支持基本类型、联合类型、交叉类型、元组等任何你需要手写的类型。
继承(Inheritance):子类继承父类,子类除了拥有父类的所有特性外,还有一些更具体的特性 多态(Polymorphism):由继承而产生了相关的不同的类,对同一个方法可以有不同的响应。比如 Cat 和 Dog 都继承自 Animal,但是分别实现了自己的 eat 方法。此时针对某一个实例,我们无需了解它是 Cat 还是 Dog,就可以直接调用 ...
C.prototype instanceof Object // true C.prototype = {}; var o2 = new C(); o2 instanceof C; // true o instanceof C; // false, because C.prototype is nowhere in o's prototype chain anymore D.prototype = new C(); // use inheritance var o3 = new D(); o3 instanceof D; //...
console.log("Error: Unauthorized update of employee!"); } } } let employee = new Employee(); employee.fullName = "Semlinker"; if (employee.fullName) { console.log(employee.fullName); } 11.3 类的继承 继承(Inheritance) 是一种联结类与类的层次模型。指的是一个类(称为子类、子接口)继承另外...
“Dynamic” means that changes to base classes at runtime are reflected immediately in all derived classes just as programmers would expect when working with single prototype inheritance.Polytype runs in Node.js, Deno and in current versions of all major browsers....
Script Type JS Dynamic JS typed code, using an inheritance prototype and replacing class properties and methods with a validation arguments function. Generates errors with wrong type information and crashes front-end UI Installation Install Script Type JS with npm npm i script-type-js Activation Conf...