为了账号安全,请及时绑定邮箱和手机立即绑定
课程 \ JavaScript进阶篇

JavaScript进阶篇

4-10 编程练习
<!DOCTYPE HTML>
<html >
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>流程控制语句</title>
<script type="text/javascript">
//第一步把之前的数据写成一个数组的形式,定义变量为 infos
var infos=[['小A','女',21,'大一'],['小B','男',23,'大三'],['小C','男',24,'大四'],['小D','女',21,'大一'],['小E','女',22,'大四'],['小F','男',21,'大一'],['小G','女',22,'大二'],['小H','女',20,'大三'],['小I','女',20,'大一'],['小J','男',20,'大三']];
//第一次筛选,找出都是大一的信息
var k=0,i;
var temp=new Array();
for(i=0;1<=10;i++)
{
if(infos[i][3]=='大一'&&infos[i][1]=='女')
document.write(infos[i][0]);
}
//第二次筛选,找出都是女生的信息
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
4-9 继续循环continue
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>continue</title>
<script type="text/JavaScript">
var mynum =new Array(70,80,66,90,50,100,89);//定义数组mynum并赋值
var i;
for(i=0;i<mynum.length;i++)
{
if(mynum[i]<60)
{
document.write("成绩不及格,不输出!"+"<br>");
continue;
}
document.write("成绩:"+mynum[i]+"及格,输出!"+"<br>");
}
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
4-8 退出循环break
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>break</title>
<script type="text/JavaScript">
var mynum =new Array(70,80,66,90,50,100,89);//定义数组mynum并赋值
var i=0;
while(i<mynum.length)
{
if(mynum[i]<60)
{
document.write("成绩"+mynum[i]+"不及格,不用循环了"+"<br>");
break;
}
document.write("成绩:"+mynum[i]+"及格,继续循环"+"<br>");
i=i+1;

}
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
4-7 来来回回(Do...while循环)
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>do...while</title>
<script type="text/javascript">
var mynum =6;//mynum初值化数值为6

do {
document.write("数字:"+mynum+"<br/>");
mynum=mynum-1;
}
while( )
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
4-6 反反复复(while循环)
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>while</title>
<script type="text/javascript">
var mynum =1;//mynum初值化数值为1
while (mynum<=5)
{
document.write("数字:"+mynum);
mynum=mynum+1;
}
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
4-5 重复重复(for循环)
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>if...else</title>
<script type="text/JavaScript">
var mymoney,sum=0;//mymoney变量存放不同面值,sum总计
for(mymoney=1; mymoney<=10 ;mymoney++)
{
sum= sum + mymoney;
}
document.write("sum合计:"+sum);
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
4-4 多种选择(Switch语句)
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>switch</title>
<script type="text/JavaScript">
var myweek =3;//myweek表示星期几变量
switch(myweek)
{
case 1:
case 2:
document.write("学习理念知识");
break;
case 3:
case 4:
document.write("到企业实践");
break;
case 5:
document.write("总结经验");
default:
document.write("周六、日休息和娱乐");
break;
}
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
4-3 多重判断(if..else嵌套语句)
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>if...else</title>
<script type="text/JavaScript">
var myage =99;//赵红的年龄为99
if(myage<=44)
{document.write("青年");}
else if(myage<=59)
{document.write("中年人");}
else if (myage<=89)
{document.write("老年人");}
else
{document.write("长寿老年人");}
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
4-1 做判断(if语句)
<!DOCTYPE HTML>
<html><head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>if语句</title>
<script type="text/JavaScript">
var mypen = "black"; //定义变量mypen,存储笔的黑色。
if(mypen==black)
{
document.write("笔是黑色的,所以购买");
}
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
3-8 编程练习
<!DOCTYPE HTML>
<html >
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>数组</title>
<script type="text/javascript">
//创建数组
var arr = ['*','##',"***","&&","****","##*"];

arr[7] = "**";
//显示数组长度
// alert(arr.length);

//将数组内容输出,完成达到的效果。
document.write(arr[0]+'<br/>');

document.write(arr[7]+'<br/>');

document.write(arr[2]+'<br/>');

document.write(arr[4]+'<br/>');


</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
3-7 二维数组
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>二维数组</title>
<script type="text/javascript">
var num= [[0,1,2],[1,2,3]];


</script>
</head>

<body>
</body>
</html>
2021-08-06 查看完整代码
3-6 了解成员数量(数组属性length)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>数组长度</title>
<script language="javascript">
var mynum=new Array(65,90,88,98);
document.write("数组的长度是:"+ mynum.length );
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
3-5 呼叫团里成员(使用数组元素)
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>使用数组</title>
<script language="javascript">
var myarr=new Array();
myarr[0]="小红";

myarr[2]="小亮";
myarr[3]="小川";
document.write("第二人的姓名是:"+ myarr[1]);
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
3-4 团里添加新成员(向数组增加一个新元素)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>增加新元素</title>
<script language="javascript">
var myarray=new Array();
myarray[0]=88;
myarray[1]=90;
myarray[2]=68;
myarray[3]=99;

document.write("数组第一个值是:"+myarray[0]+"<br>");
document.write("数组第二个值是:"+myarray[1]+"<br>");
document.write("数组第三个值是:"+myarray[2]+"<br>");

</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
3-3 谁是团里成员(数组赋值)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>数组赋值</title>
<script language="javascript">
var myarr=new Array(3);
myarr[0]=88;
myarr[1]=90;
myarr[3]=68;
document.write("数组第一个值是:"+myarr[0]+"<br>");
document.write("数组第二个值是:"+myarr[1]+"<br>");
document.write("数组第三个值是:"+myarr[2]+"<br>");
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
3-2 组团,并给团取个名(如何创建数组)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>创建数组</title>
<script type="text/JavaScript">
var myarr=new Array();
document.write("数组的第一个值:"+myarr[0]);
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
3-1 一起组团(什么是数组)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>什么是数组</title>
<script type="text/javascript">
var myarr=new Array(); //定义数组
myarr[0]=80;
myarr[1]=60;
myarr[2]=99;
document.write("第一个人的成绩是:"+myarr[0]);
document.write("第二个人的成绩是:"+myarr[1]);
document.write("第三个人的成绩是:"+myarr[2]);
</script>
</head>
<body>
</html>
2021-08-06 查看完整代码
2-13 编程练习
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>JS基础</title>
<script type="text/javascript">
var a,b,sum;
var a = 5;
var b = 100%7;
sum = a > b && a*b > 0 ;
document.write( "我认为 a 的值是:" + 5 + " b的值是:" + 2 + "sum 的值是:" + 7+"<br/>");
document.write( "答案是,第一轮计算后,a 为:"+ a +";b为:"+b +";第一次计算sum为:"+ sum +"<br/>");

sum = ( (++a) + 3 ) / (2 - (--b) ) * 3;
document.write( "再一次计算后,我认为 a 的值是:" + 4 + " b的值是:" + 1 + "sum 的值是:" + 5 +"<br/>");
document.write( "答案是,第二轮计算后,a 为:" + a + ";b为:" + b +";第二次计算sum为:"+ sum +",sum的类型也发生变化了。");

</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
2-12 保持先后顺序(操作符优先级)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>操作符优先级</title>
<script type="text/javascript">
var numa,numb,jq1;
numa=5;
numb=2;
jq1=numa + 30 >10 && numb * 3<20;
jq2=((numa + 30) / (7-numb)) * 3
document.write("jq1的值是:"+jq1+"<br>");
document.write("jq2的值是:"+jq2);
</script>
</head>
<body>
</body>
</html>
2021-08-06 查看完整代码
首页上一页12下一页尾页
意见反馈 帮助中心 APP下载
官方微信