log('hello World after 1 second.'); // output this line after 1 second return waitSecond; }).then( () => { console.log('Hell World after 2 sceond.'); // output this line after 2second }) 在ES8中又新增了更好的async,await 关键字,他可以把一个异步方法变成同步来执行。 缺点是,...
假设我们要执行两个函数,functionOne()和functionTwo(),这样functionOne()应该在执行完functionTwo()里面的一些异步语句后执行。 function functionOne(_callback){ // do some asynchronus work _callback(); } function functionTwo(){ // do some asynchronus work functionOne(()=>{ console.log("I am ...
function awaitableOperation() { return new Promise(function(resolve, reject) { // the function is executed automatically when the promise is constructed // after 1 second signal that the job is done with the result "done" setTimeout(() => resolve("done"), 1000); }); } async testPromi...
const{from}=Observableconstblock=function*(){// for each x in [1,2,3]...constx=yieldfrom([1,2,3])// wait 1 secondyieldpure({}).delay(1000)// then return the valuereturnx}// Prints 1, 2, and 3 separated by 1 second intervalsdoConcat(block).subscribe(console.log)// Waits 1...
constwaitSecond=newPromise((resolve,reject)=>{setTimeout(resolve,1000);});waitSecond.then(()=>{console.log('hello World after 1 second.');// output this line after 1 secondreturnwaitSecond;}).then(()=>{console.log('Hell World after 2 sceond.');// output this line after 2second}...
In this example, we used ourwait()function to set a 2-second delay between ourconsole.log()calls. One thing worth noticing is thatwait()doesn't stop the execution of the whole program. Our last statement was still logged just after "Hey". ...
The second parameter indicates the number of milliseconds before execution. Example Click a button. Wait 3 seconds, and the page will alert "Hello": Try it functionmyFunction() { alert('Hello'); } Try it Yourself » How to Stop the Execution...
varam =newArrayMaker('one','two'); varother =newArrayMaker('first','second'); am.getArray(); // => [ am, 'one' , 'two' ] 一个非常重要并值得注意的是出现在函数调用前面的new运算符,没有那个,你的函数就像全局函数一样,且我们创建的那些属性都将是创建在全局对象上(window),而你并不想那...
Four mutually exclusive relations are possible: less than, equal, greater than, and unordered. The last case arises when at least one operand is NaN. Every NaN shall compare unordered with everything, including itself. —“What is the rationale for all comparisons returning false for IEEE754 Na...
functionmySecond() { myDisplayer("Goodbye"); } mySecond(); myFirst(); Try it Yourself » Sequence Control Sometimes you would like to have better control over when to execute a function. Suppose you want to do a calculation, and then display the result. ...