注释与常见输出方式
输出方式
数据类型
typeof运算符
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title></title>
<style></style>
</head>
<body>
<script>
var name="asd";
var flag=true;
var falgs =false;
var user={
name:"小明",
age:18,
sex:"男"
}
alert( typeof user)
document.write(typeof user)
document.write(typeof name)
document.write(typeof flag)
console.log(typeof flag)
</script>
</body>
</html>
运算符之算术运算符
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title></title>
<style></style>
</head>
<body>
<script>
var name="asd";
var flag=true;
var falgs =false;
var user={
name:"小明",
age:18,
sex:"男"
}
alert( typeof user)
document.write(typeof user)
document.write(typeof name)
document.write(typeof flag)
console.log(typeof flag)
var numa = 4;
var numb = 2;
var numc = 5;
document.write(numa+numb);/*自增自减+1或-1*/
document.write(numb-numa);
document.write(numa*numb);
document.write(numb/numa);
document.write(numc%numa);
console.log(++numb);/*自增自减+1或-1*/
console.log(numb++);//4
console.log(numb);//5
</script>
</body>
</html>
赋值运算
比较运算
布尔运算
