梦入琼楼寒有月，行过石树冻无烟

JavaScript 计算

2022-04-21

简单的输出

1
2
3
4
5
6
7
8
9
10
11
12
13
<!DOCTYPE html>
<html>
<body>

<p id="data"></p>
<script>
document.getElementById("data").innerHTML = "Hello,world" + "!";
</script>

</body
</html>
   
<!-- 输出结果为 Hello,world! -->

简单的算数题

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
<!DOCTYPE html>
<html>
<body>

<p id="data"></p>
<script>
	var a, b, c;
	a = 1; b = 2;
    c = a + b;
	document.getElementById("data").innerHTML = "1＋2= " + c;
</script>
   
</body>
</html>

<!-- 输出结果为 1 + 2 + 3 -->

类以代数

在开发之中，类以代数通常使用变量来存放值，比如我们要表达的 data = name = user

1
2
3
4
5
6
7
8
9
10
11
12
13
14
<!DOCTYPE html>
<html>
<body>
<p id="data"></p>
<script>
	var one = 1;
	var two = 1;
	var three = 1;
	var dataone = one + two + three;
	document.getElementById('data').innerHTML = "综合:" + dataone; 
</script>
</body>
</html>
<!-- 输出：综合:3-->

一条多量

1
2
3
4
5
6
7
8
9
10
<!DOCTYPE html>
<html>
<body>
<p id="data"></p>
<script>
	var one = "1one", two = "2two", three = 11111;
	document.getElementById('data').innerHTML = one;
</script>
</body>
</html>

引号之别

1
2
3
4
5
6
7
8
9
10
11
12
<!DOCTYPE html>
<html>
<body>
<p id="data">"1" + 1 + 2：</p>
<script>
	a = "1" + 1 + 2;
	document.getElementById('data').innerHTML = a;
</script>
</body>
</html>

<!-- 输出结果为 112-->

元素

ID DA FA
innerHTML 输出 ducument.getElementByID
var 声明变量
a = 1 赋值
c = a + b 计算值

计算

ID DA
+ 加法
- 减法
* 乘法
/ 除法
% 系数
++ 递增
– 递减
** 幂
⬅️ Go back