Question

这段代码是作为previous question流量控制的工作解决方案提供的：

// an object to maintain a list of functions that can be called in sequence
// and to manage a completion count for each one
function Sequencer() {
    this.list = [];
    this.cnt = 0;
}

Sequencer.prototype.add = function(/* list of function references here */) {
    this.list.push.apply(this.list, arguments);
}

Sequencer.prototype.next = function() {
    var fn = this.list.shift();
    if (fn) {
        fn(this);
    }
}

Sequencer.prototype.increment = function(n) {
    n = n || 1;
    this.cnt += n;
}

// when calling .decrement(), if the count gets to zero
// then the next function in the sequence will be called
Sequencer.prototype.decrement = function(n) {
    n = n || 1;
    this.cnt -= n;
    if (this.cnt <= 0) {
        this.cnt = 0;
        this.next();
    }
}

// your actual functions using the sequencer object
function test_1(seq, arg1, arg2, arg3) {
    seq.increment();
        // do something with  arg1, arg2 and arg3
    seq.decrement();
}

function test_2(seq) {
    seq.increment();
        // do something       
    seq.decrement();
}

function test_3(seq) {
    seq.increment();
        // do something       
    seq.decrement();
}

// code to run these in sequence
var s = new Sequencer();

// add all the functions to the sequencer
s.add(test_1, test_2, test_3);

// call the first one to initiate the process
s.next();

在将函数添加到test_1()时，如何将参数传递给s？例如（显然不起作用）：

s.add(test_1(10,'x',true), test_2);

由于

Answer 1

如果订单不同，即test_1(arg1, arg2, arg3, seq)，您可以使用.bind：

s.add(test_1.bind(null, 10,'x',true) , test_2, test_3);

如果您无法更改订单，请传递其他功能，然后再调用test_1：

s.add(function(seq) { test_1(seq, 10,'x',true); }, test_2, test_3);

Answer 2

您可以使用Function.arguments访问函数的给定参数。

将参数传递给函数原型

2 个答案: