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来源:3-16 编程练习
lcy_18
2021-03-12 12:07:46
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>toUpperCase和toLowerCase</title>
</head>
<body>
<script>
var str="Never deter till tomorrow that which you can do today";
var index=str.indexOf('tomorrow');//补充代码
var strNew=str.substr(index,8);//补充代码
var upperStr=strNew.toUpperCase();//补充代码
document.write(upperStr);
</script>
</body>
</html>
1回答
同学你好,代码实现正确。继续加油,祝学习愉快~