Question

我正在为JXA中的某些视频编辑软件构建API - 适用于Mac OS X的自动化JavaScript .API实现的最重要的“类型”之一是TimeFrame类型。简而言之，它看起来像这样：hh:mm:ss:ff

这是我的函数，它产生类型：

function TimeFrame(val){
    if(typeof val == "string"){
        regex = /(\d\d):(\d\d):(\d\d):(\d\d)/
        arr = regex.exec(val)
        h = parseInt(arr[1])
        m = parseInt(arr[2])
        s = parseInt(arr[3])
        f = parseInt(arr[4])
        this.frames = f + s*30 + m*60*30 + h*60*60*30
    } else {
        this.frames = Math.round(val)|0
    }

    this.toString = function(){
        t = this.frames
        h = parseInt(t/30/60/60)
        m = parseInt(t/30/60%60)
        s = parseInt(t/30%60)
        f = t%30

        //Pad puts "0" infront of single digit values.
        function pad(obj) {
          return obj.toString().length > 1 ? obj : "0" + obj
        }

        return pad(h) + ":" + pad(m) + ":" + pad(s) + ":" + pad(f)
    }
    this.valueOf = function(){
        return this.frames
    }
}

该功能将按如下方式使用

var ti = new TimeFrame("00:01:32:10") //1 minute 32 seconds and 10 frames
var tf = new TimeFrame("00:01:32:12") //1 minute 32 seconds and 12 frames
var td = new TimeFrame(tf-ti)
td.toString() // returns 00:00:00:02, or 2 frames.

这只是一个如何找到两个示例区间之间差异的示例。但是，如果没有以默认方式初始化函数，则会出现问题：

var t = new TimeFrame(30)
t.toString() //returns "00:00:01:00" as expected
var t = new TimeFrame()
t.toString() //returns "00:00:00:00" as expected
t.frames = 30
t.toString() //returns "0" ?!? It should return "00:00:01:00" as above...

有谁知道为什么会这样？

我的函数中有一个非常奇怪的错误，无法弄清楚

0 个答案: