请问对吗?
来源:3-17 项目作业
神知
2021-10-30 23:33:19
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>javascript练习</title>
</head>
<body>
<script>
var str="好好学习,天天向上";
var str1=str.substring(2,4);
console.log(str1);
var str2=str.substr(2,2);
console.log(str2);
var str3=str.slice(2,4);
console.log(str3);
</script>
</body>
</html>
1回答
好帮手慕慕子
2021-10-31
同学你好,效果实现是对的,很棒!!!祝学习愉快~