1. [代码] [JavaScript]代码 !DOCTYPE htmlhtmlheadmeta charset="UTF-8"titleDocument/title/headbodyscript type="text/javascript"//第一班的学生信息var classes1=[{name:'smith',age:19,gender:1},{name:'tom',age:20,gender:1},{name:'rose
1. [代码][JavaScript]代码
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<script type="text/javascript">
//第一班的学生信息
var classes1=[
{
name:'smith',
age:19,
gender:1
},
{
name:'tom',
age:20,
gender:1
},
{
name:'rose',
age:19,
gender:0
}
];
var classes2=[
{
name:'jack',
age:21
gender:1
},
{
name:'tom',
age:20,
gender:0
},
{
name:'rose',
age:19,
gender:0
}
];
//定义一个函数来求平均年龄
function getAverageAge(arr){
//求平均年龄
var avgAge=0;
var length=arr.length;//这个班有多少人
var sum=0;
for(var i=0;i<length;i++){
var stu=arr[i]; //从数组中取出的每一个元素是对象
sum=sum+stu.age;//从每一个对象中取出年龄
}
avgAge=sum/length;
return avgAge;
}
//定义一个函数求出每个班的男女比例
function getRatio(arr){
var female=0,male=0;
var length=arr.length;
var r;
for(var i=0;i<length;i++){
var a=arr[i];
if(a.gender==1){
male++;
}else{
female++;
}
r=male/female;
return r;
}
}
alert("一班的平均年龄："+getAverageAge(classes1));
alert("二班的平均年龄："+getAverageAge(classes2));
alert("一班的男女比例："+getAverageAge(classes1));
alert("二班的男女比例："+getAverageAge(classes2));
</script>
</body>
</html>