The difference between setinterval and settimeout in JavaScript

Timer settimeout () and setinterval () are the most important and useful two methods of native JS, but many people have been mistaken for the same function: Interval time repeatedly executes the incoming handle function. But in fact, not so, since JS gives two different names, there must be a difference.

Let's take a look at both the JS manual and the English Dictionary explanation:

JS manual settimeout (): Used to call a function or evaluate an expression after a specified number of milliseconds;

English explanation timeout (): timeout, temporary rest, breaks;

JS manual setinterval (): Invokes a function or evaluation expression in the specified period (in milliseconds). The function is called continuously until the Clearinterval () is called or the window is closed;

English explanation interval (): interval; spacing; intermission;

It is not difficult to see, as long as we carefully understand the JS manual and the name of interpretation, can be very easy to separate the difference between the two. To put it simply, the difference between the two is that the settimeout () method executes the function after waiting for a specified time and executes only one incoming handle function. The SetInterval () method executes an incoming handle function after each specified interval, looping until the window or clearinterval () is closed.

The following is a look at the code but not:

var timeout=function () {
    alert (' Waits for 2s to eject, only this time! Cleartimeout can stop executing in wait time! ')
}
var interval=function () {
    alert (' Eject every 2s loop until clearinterval or close the window! ')
}
var input=document.getelementsbytagname (' input ');
    
var cleartimeoutfun=null;
var clearintervalfun=null;
    
Input[0].onclick=function () {
    cleartimeoutfun=settimeout (timeout,2000);
}
Input[1].onclick=function () {
    cleartimeout (cleartimeoutfun);
}
Input[2].onclick=function () {
    clearintervalfun=setinterval (interval,2000);
}
Input[3].onclick=function () {
    clearinterval (clearintervalfun);
}

Hands are the truth, you can write.

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