<!DOCTYPE html>
<head>
<meta charset="UTF-8">
<title>算数运算符</title>
<script type="text/javascript">
var a = 3.5; // = 把右边的赋值给左边的变量
var b = 2;
// var res1 = a + b;
// var res2 = a - b;
// var res3 = a * b;
// var res4 = a / b;
// var res5 = a % b;//求余
// console.log(res1);
// console.log(res2);
// console.log(res3);
// console.log(res4);
// console.log(res5);
// console.log(a+b);
// a++;// a = a + 1;
// b++;//自增
// console.log(a);
// console.log(b);
// a--;// a = a - 1;
// b--;
// console.log(a);
// console.log(b);
// + - * / %
// += -= *= /= %=
// a += 2; //a=a+2;
// a -= 2; //a=a-2;
// a *= 2; //a=a*2;
// a /= 2; //a=a/2;
// a %= 2; //a=a%2;
// console.log(a);
var res1 = "Hello" + "World"; //HelloWorld
var res2 = "Hello" + 100; //"Hello" + "100" Hello100
var res3 = 100 + "Hello"; //100Hello
var res4 = "100" + 100; //100100
var res5 = 100 + 100 + "sikiedu.com"; //100100sikiedu.com ??? 不对
var res6 = "sikiedu.com" + 100 + 100; //sikiedu.com100100
console.log(res1);
console.log(res2);
console.log(res3);
console.log(res4);
console.log(res5);//200sikedu.com
console.log(res6);
var res7 = "" + a + b; //3.52;
console.log(res7);//"3.52"
</script>
</head>
<body>
</body>
</html>
运算符
赋值运算符 =
算术运算符 + - * / % ++ --
赋值运算符 += -= *= /= %=
字符串相加
字符串和其他类型数据相加
