class
// es5 be inherited through the prototype
function Pa (X, Y) {
// constructor write attribute
in this.x = X;
this.y from Y =;
}
// write the public properties or methods prototype
Pa.prototype.say function = () {
the console.log (in this.x);
}
// a new new eXAMPLES example methods and constructors will have on the properties of the prototype
the let P = Pa new new ( "a", 2);
p.say (); // a
// es6 in es5 is different with the same wording
// es5 prototype object constructor and write separately,
// es6 class is all written in
class Pa {
// constructor is the constructor es5 in the
constructor (x, y) {
in this.x = X;
this.y from Y =;
}
// do not need delimiter, direct write prototyping
say () {
the console.log (in this.x);
}
}
the let P = Pa new new ( "A", 2);
p.say (); // A
the console.log (== Pa.prototype.constructor Pa); // to true
// Pa is that the constructor
Internal methods of the class not enumerable
ES5 //
function Pa () {};
Pa.prototype.b = ". 1"
the let P = Pa new new ();
the console.log (Object.keys (P)); // [] attribute names on the object does not traverse It traverses properties on prototype object
console.log (Object.keys (Pa.prototype)); // [ "b"] prototype object is the object listed Key
// ES6
class {Ku-
C () {
Console. log (132);
}
};
the console.log (Object.keys (Ku.prototype)); // internal [] of all defined class methods are not enumerable
Pa {class
}
// equivalent to the
class {Pa
constructor () {}
}
class above properties
{Ku-class
constructor () {
in this.x =. 8;
this.y from =. 9; // return the best attributes
}
A =. 1; // attribute instance directly =
@ B: 2 not written
c () {
the console.log ( "55");
}
}
the let K = Ku-new new ();
the console.log (KA); //. 1
the console.log (KX); //. 8
KC (); // 55
// Object of hasOwnProperty () method returns a Boolean value, determines whether a specific object contains its own (non-inherited) properties.
console.log (k.hasOwnProperty ( "x") ); // true own constructor or
the console.log (k.hasOwnProperty ( "A")); // to true
the console.log (k.hasOwnProperty ( "C ")); // false method on the prototype
Static method
Static method // example which is not inherited, but directly by calling class
// used in the former method, plus the static keyword
class {Pa
static See () {
the console.log ( "look");
}
say () {
the console.log ( "hahaha ~");
}
}
Pa.see (); // look
the let P = Pa new new (); // class needs new new
p.say (); // hahaha ~
P. see (); //p.see is not a function instance is not a static method
// static properties
// ES6 clear that internal Class only static methods, no static properties.
{Pa} class;
Pa.a = 1;
the let P = Pa new new ();
the console.log (Pa.a); // Class 1 directly call the static properties
console.log (pa); // undefined example not inherited static Attributes