The execution process of javascript new fun_js object-oriented

(1) Create a new object and let this pointer point to it;
(2) Assign all members of the function’s prototype object to this new object;
(3) Execute the function body and modify this object Perform initialization operations;
(4) returns the object created in (1).

Copy code The code is as follows:

function BB(a){
this.aa();
alert("s");

}
//alert(typeof BB.prototype.constructor);
BB.prototype.aa= function(){alert("sss");}
var nn=new BB("cc");
//var nn={};BB.apply(nn)
//nn= BB.prototype;

alert(nn.constructor);