请老师检查，谢谢
来源：4-11 编程练习
派大星爱学习
2022-07-05 13:50:17
<!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>编程练习04</title>
<style>
.red {
border: 1px solid red;
}
</style>
</head>
<body>
姓名：<input type="text"> <span></span>
<script>
var text = document.querySelector('input');
var span = document.querySelector('span');
text.onfocus = function () {
span.innerText = '请输入您的姓名';
}
text.onblur = function () {
if (!text.value) {
span.innerText = '用户名不能为空';
text.className = 'red';
} else {
span.innerText = ' ';
text.className = ' ';
}
}
</script>
</body>
</html>
写回答
1回答
-
好帮手慕小李
2022-07-05
同学你好，代码思路是对的很棒，继续努力，祝学习愉快！
0
相似问题