我正在尝试创建一个包含标题,文本区域,发布按钮和清除按钮的HTML表单。我的目的是在用户单击“清除”按钮时清除文本区域,但是在此之前会出现警告,询问用户是否确定要清除文本。如果用户键入OK,则要删除的文本区域;如果用户键入Cancel,则要取消的方法。
我尝试了以下代码,但是我注意到,无论我键入什么输入或按下的按钮,默认情况下都会删除文本区域中的文本。如何防止这种情况并使其起作用?
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"/>
<link rel="stylesheet" href="global.css">
</head>
<body>
<form >
<input type="text" id="title" name="title">
<textarea id="blog_textarea" name="blog" placeholder="Your Text">
</textarea>
<br><button type="submit" id="post" name="submission" value="Submit">Post</button>
<button id="clear_button" onclick="clearFun()" >Clear</button>
</form>
<p id="demo"></p>
<script>
function clearFun() {
var par_output="";
var txt = prompt("To confirm, please type OK, or to stay type Cancel ");
if (txt == "OK" || "ok") {
document.getElementById("blog_textarea").value = "";
} else {
par_output = "Please type OK to confirm or Cancel";
}
document.getElementById("par_output").innerHTML = demo;
}
</script>
</body>
</html>
也可以使用there is Jsfiddle
非常感谢你们
您需要分别写两个条件,并且清除表单标签也有效
if (txt == "OK" ||txt == "ok")
这应该起作用:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
</head>
<body>
<textarea id="textarea"></textarea>
<br />
<button id="clearbutton">Clear</button>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
$('#clearbutton').click(async () => {
const clear = await prompt('Clear? Type ok');
if (clear.toLowerCase() === 'ok') {
$('#textarea').val('');
}
});
</script>
</body>
</html>
使用普通JavaScript:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
</head>
<body>
<textarea id="textarea"></textarea>
<br />
<button id="clearbutton">Clear</button>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
document
.getElementById('clearbutton')
.addEventListener('click', async () => {
const clear = await prompt('Clear? Type ok');
if (clear.toLowerCase() === 'ok') {
document.getElementById('textarea').value = '';
}
});
</script>
</body>
</html>