Instance code for timers in JavaScript

1. Set Timer

Syntax: setinterval (function, time)

Attention:

function cannot be written with parentheses

SetInterval (fn,1000)//correct SetInterval (FN (), 1000)//Error

The minimum time setting is not less than 14ms

2. Clear Timer

Syntax: Clearinterval (the name of the timer cleared)

3. Case study

JS part

Window.onload =function () { Vartimer =null; Varnum = 0; Vari = 0; vararr=[' red ', ' #FF9D0C ', ' #DBFF0D ', ' #3BFF0D ', ' #0DFFA2 ', ' #0DE8FF ', ' #0D52FF ', ' #210DFF ', ' #930DFF ', ' #FF0DB4 '] Varstart = document.getElementById (' start '); Varstop = document.getElementById (' Stop '); Varprizedraw = document.getElementById (' Prizedraw '); Start.onclick =function () { Clearinterval (timer); Timer = setinterval (function () { num = Math.floor (math.random () *100+1); PrizeDraw.style.backgroundColor = Arr[i]; i++; if (i==9) { i = 0; }; prizedraw.innerhtml = num; },100); } Stop.onclick =function () { Clearinterval (timer); } }

CSS Section

#prizeDraw { width:100px; height:100px; Background:rgba (255,68,253,0.5); font-size:30px; Text-align:center; line-height:100px; }

HTML section

<divid= "Prizedraw" ></div> <inputtype= "button" value= "Starting" id= "Start" > <inputtype= "button" value= "Pause" id= "Stop" >

Code Analysis:

Note that when running the timer to clear the timer first, otherwise, if the timer has been clicked, the timer will run multiple, stop also stop;

Clearinterval () can accept the cleared value of NULL;

An application that stores content in an array.

Original link: http://www.cnblogs.com/huyuzhu/p/6200840.html