第javascript代碼實(shí)現(xiàn)簡易計(jì)算器html部分的話就是吧所有數(shù)字定義為一個class名字，把所有運(yùn)算符號定義為一個class以及定義兩個input來存放運(yùn)算符

script

lis=document.querySelectorAll("#boxul.num")//獲取所有的數(shù)字

opcr=document.querySelectorAll("#boxul.opcr")//獲取運(yùn)算符

for(vari=0;ilis.length;i++){//遍歷所有的數(shù)字

lis[i].onclick=function(){

input1.value+=parseInt(this.innerHTML)//點(diǎn)擊input1顯示

//遍歷所有的運(yùn)算符

for(leti=0;iopcr.length;i++){

opcr[i].onclick=function(){

if(text1.value==""){//當(dāng)存放第一個值為空時候

text1.value=input1.value//存放第一個值

input1.value=""http://input框里的值為空

per.value=this.innerHTML;//存放符號的值為空

}else{

text1.value=eval(text1.value+per.value+input1.value)//不是空的時候計(jì)算

per.value=this.innerHTML;//存放符號的值為點(diǎn)擊的值

input1.value=""http://input框里的值為空

//等于

resule.onclick=function(){

input1.value=eval(text1.value+per.value+input1.value)//計(jì)算里面的值

per.value=""http://清空存放per的值

text1.value=""http://input框里的值為空

//點(diǎn)擊清空所有

returnZero.onclick=function(){

input1.value=""

per.value=""

text1.value=""

/script

完整部分

!DOCTYPEhtml

htmllang="en"

head

metacharset="UTF-8"

metaname="viewport"content="width=device-width,initial-scale=1.0"

metahttp-equiv="X-UA-Compatible"content="ie=edge"

title簡易計(jì)算器/title

style

#box{

background-image:linear-gradient(120deg,#84fab00%,#8fd3f4100%);

width:500px;

height:420px;

margin:auto;

margin-top:200px;

position:relative;

.reckon{

width:280px;

height:200px;

background-image:linear-gradient(120deg,#d4fc790%,#96e6a1100%);

position:absolute;

top:100px;

left:100px;

border:5pxsolid#2a2b2c

#input1{

background-image:linear-gradient(totop,#cfd9df0%,#e2ebf0100%);

border:none;

width:220px;

height:8px;

float:right;

margin-top:10px;

margin-right:20px;

outline:none;

padding:10px

ulli{

float:left;

list-style:none;

margin:4px2px;

border-radius:3px;

background-image:linear-gradient(120deg,#a1c4fd0%,#c2e9fb100%);

box-shadow:2px2px#ccc;

color:#fff;

font-weight:"楷體";

width:50px;

height:30px;

text-align:center;

line-height:30px;

ul{

margin-top:5px;

ulli:hover{

opacity:0.7;

/style

/head

body

divid="box"

divid="reckon"

inputtype="text"id="input1"

li7/li

li8/li

li9/li

li+/li

li4/li

li5/li

li6/li

li-/li

li1/li