北大青鸟 使用JQuery制作特效 第一章(上机练习
练习一丶——统计包含“a”或“A”的字符串个数
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<script type="text/javascript">
var count = 0;
var fum = ["America","Greece","Britain","Canada","China","Egypt"];
for(var i in fum){
document.write(fum[i]+"<br/>");
if(fum[i].indexOf("a") != -1){
count++;
}
}
document.write("共有"+count+"个字符中包含a或A");
</script>
</body>
</html>
练习二丶调试训练
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<script type="text/javascript">
var t = prompt("请输入时间");
if(t>=6 && t<=12){
document.write("上午好,欢迎来到贵美");
var str="";