JavaScript creation object and construction class implementation code_js object-oriented

Create an object
Java code

Copy code The code is as follows:

Using json (javaScript Object Notation) to create objects has the same effect as above.
Java code

Copy code The code is as follows:

function sayLoudly(){
alert(this.firstName.toUpperCase());
}
var newObject={
firstName:"frank",
sayName:function(){alert(this.firstName);},
sayLoudly:sayLoudly
};
//You can also do this
var newObject={
firstName: "frank",
sayName:function(){alert(this.firstName) ;},
sayLoudly:sayLoudly,
lastName:{
lastName:"ziggy",
sayName:function(){alert(this.lastName);}
}
} ;
newObject.lastName.sayName();

This is ok
Java code

Copy code The code is as follows:

function sayLoudly(){
alert(this.name.toUpperCase());
}
function sayName(){
alert(this.name);
}
var newObject={
name:"frank",
sayName:sayName,
sayLoudly:sayLoudly,
lastName:{
name:"ziggy",
sayName:sayName
}
};
newObject.lastName.sayName();

Classes in JavaScript, as well as constructors method. . .
Java code

Copy code The code is as follows:

function newClass(){
alert("constructor");
this.firstName="frank";
this.sayName=function(){alert(this.firstName);}
// return this;
}
//var nc=newClass();
var nc=new newClass();
//nc.firstName="ziggy"; is ok
nc.sayName();

You can also construct a class like this
Java code

Copy code The code is as follows:

function newClass(){
this.firstName="frank";
}
newClass.prototype.sayName=function(){
alert(this.firstName);
}
var nc=new newClass();
nc.firstName="ziggy";
nc.sayName();
var nc2=new newClass();
nc2.sayName ();

Usually prototypes are used to add methods, so that no matter how many instances there are, there is only one sayName method in the memory.