Question

我有一个大小为3的数组。我需要在数组值更改时动态调用函数。有什么想法吗？

var arr = ["","",""];

arr[0] = 'first value is chagned';
arr[1] = 'second value is chagned';


function arrFunction(){
    console.log('Array value changed')
}

预期输出

数组值已更改

我知道我们可以通过直接调用函数来实现这一点，如下所示。作为参考，我提供了这些输入。我不能直接调用下面的函数

var arr = ["","",""];

arr[0] = 'first value is chagned';
arrFunction()
arr[1] = 'second value is chagned';
arrFunction()

function arrFunction(){
    console.log('Array value changed')
}

Answer 1

如果你的目标支持Proxies这很容易做到：

let observe = (obj, fn) => new Proxy(obj, {
    set(obj, key, val) {
        obj[key] = val;
        fn(obj)
    }
});

arr = observe(['', '', ''], arr => {
    console.log('arr changed! ', arr)
});

arr[0] = 'first value is chagned';
arr[1] = 'second value is chagned';

数组节点js中数据更改的事件侦听器

1 个答案: