我正在玩对象和构造函数等内容,我想知道是否有一种方法可以根据变量的初始定义来绑定一个值。我有以下代码:
typescript
let cr = "create",
ap = "apply",
$this = {
set: (prop, value) => {
this[prop] = value;
}
};
function creator() {
this.$ = (array: Object[]) => {
array.forEach((kp: Object) => {
let key = Object.keys(kp)[0];
let val = kp[Object.keys(kp)];
$this[key] = val;
creator.create(key, { value: val });
});
};
this.apply = (...objects: Object[]) => {
objects.forEach((obj: Object) => {
creator.call(obj);
});
};
}
function create(obj) {
function createValues(arr) {
let instance: Object = new obj();
let vals: any[] = [];
arr.forEach(name => {
vals.push(instance[name]);
});
return vals;
}
let names: string[] = Object.getOwnPropertyNames(new obj());
let values: string[] = createValues(names);
return combineArrays(names, values);
}
function combineArrays(arr1, arr2): { $?: any } { // the question mark removes an IDE error
let newObj: Object = {};
arr1.forEach(prop => {
newObj[prop] = arr2[arr1.indexOf(prop)];
});
return newObj;
}
Object.prototype.create = function(prop, options) {
return Object.defineProperty(this, prop, options);
};
create(creator).$([
{ hi: "hi" },
{ bye: $this["hi"] } // this is the important stuff
]);
我想知道在$this
变量的set
函数中,是否有一种方法可以检测它是如何被设置的,从而确定该值是否已更改,因此它的值应该是新的(如果这有任何意义的话)?比方说你有这样一个函数:
let $this = {
set: function(prop, value) {
this[prop] = value;
}
}
let name = 'Ezra';
$this['name'] = name;
// then :
name = 'Bob';
// change $this.name too, so then:
console.log($this.name);
// >> 'Bob'
我相信这被称为数据绑定,但我不确定如何在不创建无数代理的情况下完成它。