1.实现基本计算器功能，如图
2.逻辑代码
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>计算器</title>
<!--设置样式-->
<style>
.showdiv{
text-align: center;
margin:auto;/*设置居中*/
border: solid 1px;
width: 400px;
height: 500px;
border-radius: 10px;/*设置边框角度*/
}
input[type="text"]{
margin-top: 10px;
width: 380px;
height: 40px;
font-size: 40px;
}
input[type="button"]{
margin: 10px;
margin-top: 20px;
width: 60px;
height: 80px;
font-size: 40px;
font-weight: bold;
}
</style>
<!--设置js代码-->
<script type="text/javascript">
/*将按钮的值赋值给输入框*/
function num(btn){
//把不能为零去掉
if(document.getElementById("inp").value.match("除数")){
document.getElementById("inp").value = "";
}
//获取button按钮的value
var num = btn.value;
console.log(num +" " +typeof(num))
//将值赋值给text文本框
switch(num){
case "c":
document.getElementById("inp").value = "";
break;
case "=":
if(document.getElementById("inp").value.match("/")){
if(document.getElementById("inp").value.split("/")[1] == "0"){
document.getElementById("inp").value = "除数不能为零";
}else{
document.getElementById("inp").value = eval(document.getElementById("inp").value);
}
break;
}else{
document.getElementById("inp").value = eval(document.getElementById("inp").value);
break;
}
default:
document.getElementById("inp").value = document.getElementById("inp").value+num;
break;
}
}
</script>
</head>
<body>
<div class = "showdiv">
<input type="text" name="" id="inp" value="" readonly="readonly"/><br />
<input type="button" name="" id="" value="0" onclick="num(this)"/>
<input type="button" name="" id="" value="1" onclick="num(this)"/>
<input type="button" name="" id="" value="2" onclick="num(this)"/>
<input type="button" name="" id="" value="3" onclick="num(this)"/><br />
<input type="button" name="" id="" value="4" onclick="num(this)"/>
<input type="button" name="" id="" value="5" onclick="num(this)"/>
<input type="button" name="" id="" value="6" onclick="num(this)"/>
<input type="button" name="" id="" value="7" onclick="num(this)"/><br />
<input type="button" name="" id="" value="8" onclick="num(this)"/>
<input type="button" name="" id="" value="9" onclick="num(this)"/>
<input type="button" name="" id="" value="+" onclick="num(this)"/>
<input type="button" name="" id="" value="-" onclick="num(this)"/><br />
<input type="button" name="" id="" value="*" onclick="num(this)"/>
<input type="button" name="" id="" value="/" onclick="num(this)"/>
<input type="button" name="" id="" value="=" onclick="num(this)"/>
<input type="button" name="" id="" value="c" onclick="num(this)"/>
</div>
</body>
</html>
