采用call方式实现js继承

//采用call方式实现js继承 
function A(color) { 
this.Acolor = color; 
this.AshowColor = function() { 
document.writeln("Acolor: " + this.Acolor); 
} 
} function B(color, name) { 
A.call(this, color); 
this.Bname = name; 
this.BshowName = function() { 
document.writeln("Bname: " + this.Bname); 
} 
} 
var objA = new A("red"); 
objA.AshowColor(); 
document.writeln("----------------"); 
var objB = new B("black", "demo"); 
objB.AshowColor(); 
objB.BshowName(); 
document.writeln("----------------");