Question

var CHECK_ITERATIONS = 5;

function NewCheckEvent(device, account, eventId, url) {
    this.iteration = 0;
    this.status = "checking";
    this.device = device;
    this.url = url;
}   

NewCheckEvent.prototype.runCheckLoop = function() {
    if (this.iteration < CHECK_ITERATIONS) {
         this.iteration = this.iteration++;
         console.log('iteration ' + this.iteration);
          setTimeout(function (){
              this.runCheckLoop();
          }.bind(this), 1000);
    }
}


var bob = new NewCheckEvent(14245, 92136, "9f2b2d3f-45d4-a82f-b12e082b1164", "dddd");
console.log(bob);
bob.runCheckLoop();

one@localhost ~ $ node try.js 
{ iteration: 0, status: 'checking', device: 14245, url: 'dddd' }
iteration 0
iteration 0
iteration 0

当runCheckLoop在setTimeout中调用自身时，怎么会没有增加this.iteration？我该如何解决这个问题？

Answer 1

this.iteration = this.iteration++;

this.iteration++递增属性，但随后返回原始值。左侧的赋值将其设置回原始值。也许你只想

this.iteration++;

Answer 2

行中的问题

this.iteration = this.iteration++;

这里你实际上说：设置this.iteration = this.iteration然后递增;因此，您将旧值分配回来。它应该只是

this.iteration++;

代替。

当方法调用自身时，Javascript- this.increment不会递增

2 个答案: