js对象构造方法

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第一种 var Car = function() { this.wheels = 4; this.engines = 1; this.seats = 1; };第二种 var Car = function(wheels, seats, engines) { this.wheels = wheels; this.seats = seats; this.engines = engines; };第三种 var car = { “wheels”:4, “engines”:1, “seats”:5 };