1. 字符串:

<!DOCTYPE html>
<html>
<body> <script>
var apple = "苹果";
var banana = "香蕉";
var orange = "橘子";
var name1 = "小明";
var name2 = "小红"; document.write(name1 + "说:老师我想吃" + apple + "<br>");
document.write(name2 + "说:老师我想吃" + banana + "和" + orange);
</script> </body>
</html>

2. 数值

js中,数值类型比较简单,不区分整型浮点型等数字类型。就是这个数,带不带小数点,对js来说都是一样进行识别。

<!DOCTYPE html>
<html>
<body>

<script>
var a = 1;
var b = 2.3;
var c = a + b;
var name1 = "小明";
var name2 = "小红";

document.write(name1 + "问" + name2 + ":" + a + "+" + b + "等于几呀?" + "<br>");
document.write(name2 + "回答说:" + a + "+" + b + "等于" + c + "呀!" + "<br>");

</script>

</body>
</html>

难道js中,字符串和数值可以直接相加进行拼接吗?

实验:

<!DOCTYPE html>
<html>
<body>

<script>
var a = 1;
var b = 2.3;
var c = a + b;
var name1 = "小明";
var name2 = "小红";

document.write(name1 + "问" + name2 + ":" + a + "+" + b + "等于几呀?" + "<br>");
document.write(name2 + "回答说:" + a + "+" + b + "等于" + c + "呀!" + "<br>");

document.write(a + name1 + b + name2);

</script>

</body>
</html>  

结果:

小明问小红:1+2.3等于几呀?
小红回答说:1+2.3等于3.3呀!
1小明2.3小红

可以的。

3. 布尔类型

真和假,分别用true和false表示。

4. 数组

<!DOCTYPE html>
<html>
<body> <script>
// 方法1
var i;
var cars1 = new Array();
cars1[0] = "Audi";
cars1[1] = "BMW";
cars1[2] = "Volvo"; for (i=0;i<cars1.length;i++)
{
document.write(cars1[i] + "<br>");
} document.write("<br>"); // 方法2
var cars2 = new Array("Audi", "BMW", "Volvo");
for (i=0;i<cars2.length;i++)
{
document.write(cars2[i] + "<br>");
}
</script> </body>
</html>

结果:

Audi
BMW
Volvo Audi
BMW
Volvo

5. JavaScript对象

<!DOCTYPE html>

<html>
<body>

<script charset = "utf-8">
var info = {
name: "小明",
age: 63,
addr: "象牙山村156号",
}

// js对象有两种寻址方式
// 寻址1
document.write(info.name + "<br>");
// 寻址2
document.write(info["addr"] + "<br>");

</script>

</body>
</html>

 

一开始运行出来,中文是乱码,在<script charset = "utf-8">中,加入charset = "utf-8"后,解决了。