JavaScript 组成工厂
示例
“优先于继承而不是继承”是一种重要且流行的编程原理，用于将行为分配给对象，而不是继承许多通常不需要的行为。
行为工厂
var speaker = function (state) {
var noise =state.noise|| 'grunt';
return {
speak: function () {
console.log(state.name + ' says ' + noise);
}
};
};
var mover = function (state) {
return {
moveSlowly: function () {
console.log(state.name + ' is moving slowly');
},
moveQuickly: function () {
console.log(state.name + ' is moving quickly');
}
};
};对象工厂
var person = function (name, age) {
var state = {
name: name,
age: age,
noise: 'Hello'
};
return Object.assign( //合并我们的“行为”对象
{},
speaker(state),
mover(state)
);
};
var rabbit = function (name, colour) {
var state = {
name: name,
colour: colour
};
return Object.assign(
{},
mover(state)
);
};用法
var fred = person('Fred', 42);
fred.speak(); //输出：Fred说你好
fred.moveSlowly(); //输出：Fred动作缓慢
var snowy = rabbit('Snowy', 'white');
snowy.moveSlowly(); //输出：Snowy移动缓慢
snowy.moveQuickly(); //输出：Snowy快速移动
snowy.speak(); //错误：snowy.speak不是函数