JavaScript和线程

使用HTML5"side-specs" 不再需要使用setTimeout(),setInterval()等来破解javascript.

HTML5和Friends介绍了javascript Web Workers规范.它是一个异步和独立运行脚本的API.

指向规范和教程的链接.

JavaScript中没有真正的线程.JavaScript是可塑的语言,它允许你模仿它的一部分.这是我前几天遇到的一个例子.

Javascript中没有真正的多线程,但您可以使用setTimeout()异步AJAX请求获得异步行为.

你到底想要完成什么？

这里只是一种在Javascript中模拟多线程的方法

现在我将创建3个线程,它们将计算数字加法,数字可以除以13,数字可以除以3到10000000000.这三个函数不能像Concurrency那样同时运行.但是我将向您展示一个技巧,使这些函数在同一时间递归运行:jsFiddle

这段代码属于我.

身体的一部分

    

    Counting summation of numbers till 10000000000 = 0


    Counting numbers can be divided with 13 till 10000000000 = 0


    Counting numbers can be divided with 3 till 10000000000 = 0

Javascript部分

var _thread1 = {//This is my thread as object
    control: false,//this is my control that will be used for start stop
    value: 0, //stores my result
    current: 0, //stores current number
    func: function () {   //this is my func that will run
        if (this.control) {      // checking for control to run
            if (this.current < 10000000000) {
                this.value += this.current;   
                document.getElementById("1").innerHTML = this.value;
                this.current++;
            }
        }
        setTimeout(function () {  // And here is the trick! setTimeout is a king that will help us simulate threading in javascript
            _thread1.func();    //You cannot use this.func() just try to call with your object name
        }, 0);
    },
    start: function () {
        this.control = true;   //start function
    },
    stop: function () {
        this.control = false;    //stop function
    },
    init: function () {
        setTimeout(function () {
            _thread1.func();    // the first call of our thread
        }, 0)
    }
};
var _thread2 = {
    control: false,
    value: 0,
    current: 0,
    func: function () {
        if (this.control) {
            if (this.current % 13 == 0) {
                this.value++;
            }
            this.current++;
            document.getElementById("2").innerHTML = this.value;
        }
        setTimeout(function () {
            _thread2.func();
        }, 0);
    },
    start: function () {
        this.control = true;
    },
    stop: function () {
        this.control = false;
    },
    init: function () {
        setTimeout(function () {
            _thread2.func();
        }, 0)
    }
};
var _thread3 = {
    control: false,
    value: 0,
    current: 0,
    func: function () {
        if (this.control) {
            if (this.current % 3 == 0) {
                this.value++;
            }
            this.current++;
            document.getElementById("3").innerHTML = this.value;
        }
        setTimeout(function () {
            _thread3.func();
        }, 0);
    },
    start: function () {
        this.control = true;
    },
    stop: function () {
        this.control = false;
    },
    init: function () {
        setTimeout(function () {
            _thread3.func();
        }, 0)
    }
};

_thread1.init();
_thread2.init();
_thread3.init();

我希望这种方式会有所帮助.

您可以使用Narrative JavaScript,一种将您的代码转换为状态机的编译器,有效地允许您模拟线程.它通过在允许您在单个线性代码块中编写异步代码的语言添加"让步"运算符(标记为" - >")来实现.