JavaScript学习

1.if...else的学习:

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8" />
        <title>if...else
        </title>
        <script type="text/javascript">
            var ticket = true;
            if (ticket) {
                document.write("有票,看电影")
            } else{
                document.write("没有票,看不了电影")
            }
        </script>
    </head>
    <body>
    </body>
</html>

2.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");
 break;
 default:
 document.write("周六、日休息和娱乐");
}
</script>
</head>
<body>
</body>
</html>

3.for循环语句:

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>if...else</title>
<script type="text/JavaScript">
var 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>

4.While语句:

<!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>

5.Do...While语句:

do while结构的基本原理和while结构是基本相同的，但是它保证循环体至少被执行一次。因为它是先执行代码，后判断条件，如果条件为真，继续循环。

<!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( mynum <= 0 )
    </script>
</head>
<body>
</body>
</html>

6.退出循环Break;

7.退出本次循环Continue;

 

posted on 2017-02-04 17:29  玉思盈蝶  阅读(141)  评论(0)  编辑  收藏  举报

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