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制作一个计算器效果图如下：
一言不合上代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Calculator</title>
<style>
/* 主体 */
.counter {
width: 396px;
height: 486px;
background-color: #F2F2F2;
border: 1px solid #C2C3C6;
margin: 50px auto;
}
/* 显示框 */
#box {
height: 70px;
width: 336px;
background-color: #323232;
border: none;
margin: 40px 25px 32px 25px;
font: 700 40px/70px "微软雅黑";
color: #ffffff;
padding-right: 10px;
}
/* 功能区 */
.funct {
padding: 0 20px;
position: relative;
}
/* 按钮样式 */
.funct input {
height: 40px;
width: 60px;
margin: 10px 10px;
font: 400 20px/40px "微软雅黑";
}
/* 清除按钮样式 */
.funct #res {
width: 150px;
}
/* + - = . 按钮浮动 */
#add, #reduce, #round, #sum {
position: absolute;
right: 0px;
bottom: 0px;
}
/* 减号位置 */
#reduce {
right: 30px;
top: 60px;
}
/* 加号位置 */
#add {
right: 30px;
top: 120px;
}
/* 等于号位置 */
#sum {
height: 100px;
right: 30px;
bottom: 0px;
}
/* 小数点位置 */
#round {
right: 120px;
bottom: 0px;
}
/* 0 */
#zero {
width: 150px;
}
/* 数字区 */
.numb {
width: 280px;
}
</style>
<script>
window.onload = function(){
// 数据容器
var left = 0; //被除数
var right = 0; //除数
var sum = 0; //和
var numb = 0; //此变量用来限制点的输入
// 获取id并返回
function $(id){
return document.getElementById(id);
}
// 运算函数
function operation(id){
if( $("box").value != "0"){
if(left == 0)
{
$("box").value = $("box").value + $(id).value;
left = parseFloat($("box").value);
}
}
//numb 转为number类型 让点可以再输入一次
numb = 0;
}
// 数字盘函数
function figure(id){
// 判断被除数是否有值
if(left == 0)
{
// 改变value默认值
if ($("box").value === "0" ) {
$("box").value = $(id).value;
}else{
$("box").value = $("box").value + $(id).value;
}
}else{
$("box").value = $("box").value + $(id).value;
var str = $("box").value;
var num = "";
// 获取第二次输入的数字
for (var i = 0; i < str.length; i++) {
// 判断加减乘除
if(str[i]== "+"){
for (var j = i + 1; j < str.length; j++) {
num+=str[j];
};
right = parseFloat(num);
}else if(str[i]== "-"){
for (var j = i + 1; j < str.length; j++) {
num+=str[j];
};
right = parseFloat(num);
}
else if(str[i]== "*"){
for (var j = i + 1; j < str.length; j++) {
num+=str[j];
};
right = parseFloat(num);
}
else if(str[i]== "/"){
for (var j = i + 1; j < str.length; j++) {
num+=str[j];
};
right = parseFloat(num);
}
};
}
// 清空所有数据
if(sum != 0){
left = 0;
right = 0;
sum = 0;
numb = 0;
$("box").value = $(id).value;
}
}
// 数字键盘区----------------------------------------------------------开始
$("one").onclick = function(){
figure("one");
}
$("two").onclick = function(){
figure("two");
}
$("three").onclick = function(){
figure("three");
}
$("four").onclick = function(){
figure("four");
}
$("five").onclick = function(){
figure("five");
}
$("six").onclick = function(){
figure("six");
}
$("seven").onclick = function(){
figure("seven");
}
$("eight").onclick = function(){
figure("eight");
}
$("nine").onclick = function(){
figure("nine");
}
$("zero").onclick = function(){
figure("zero");
}
// 数字键盘区----------------------------------------------------------结束
//功能区-----------------------------------------------------------开始
// 加
$("add").onclick = function(){
operation("add");
}
//减
$("reduce").onclick = function(){
operation("reduce");
}
// 乘
$("ride").onclick = function(){
operation("ride");
}
// 除
$("division").onclick = function(){
operation("division");
}
// 点
$("round").onclick = function(){
// 限制点的输入
if(numb === 0 && sum == 0){ //numb值等于0 类型等于number
$("box").value = $("box").value + $("round").value;
numb = ($("box").value); //numb赋值为字符串
}
}
// 清除
$("res").onclick = function(){
if($("box").value != "0")
{
left = 0;
right = 0;
sum = 0;
numb = 0;
$("box").value = "0";
}
}
// 求和
$("sum").onclick = function(){
var symbol = "";
if(left != 0 && right != 0){
for (var i = 0; i < $("box").value.length; i ++ ) {
symbol = $("box").value[i];
if(symbol == "+"){
sum = left + right;
$("box").value = sum;
}else if(symbol == "-"){
sum = left - right;
$("box").value = sum;
}
else if(symbol == "*"){
sum = left * right;
$("box").value = sum;
}
else if(symbol == "/"){
sum = left / right;
$("box").value = sum;
}
};
}
}
}
// 功能区--------------------------------------------------------------------------结束
</script>
</head>
<body>
<div class="counter">
<input type="text" id="box" style="text-align:right" readOnly="true" value="0">
<div class="funct">
<input type="reset" id="res" value="C">
<input type="button" id="division" value="/">
<input type="button" id="ride" value="*">
<input type="button" id="add" value="+">
<input type="button" id="reduce" value="-">
<input type="button" id="round" value=".">
<input type="button" id="sum" value="=">
<div class="numb">
<input type="button" id="one" value="1">
<input type="button" id="two" value="2">
<input type="button" id="three" value="3">
<input type="button" id="four" value="4">
<input type="button" id="five" value="5">
<input type="button" id="six" value="6">
<input type="button" id="seven" value="7">
<input type="button" id="eight" value="8">
<input type="button" id="nine" value="9">
<input type="button" id="zero" value="0">
</div>
</div>
</div>
</body>
</html>