HTML Required 屬性是一個布爾屬性,它指定必須在提交表單之前填寫 input 元素。此屬性與以下元素一起使用:
- <input>
- <select>
- <textarea>
<input>
我們可以輕鬆地將 required 屬性與 <input> 元素一起使用,如以下語法所示:
<input required>
示例
<html>
<head>
<title>
Example of required attribute with input element
</title>
<style>
div
{
padding:10px 0;
}
</style>
<head>
<body>
<form>
<div>
<label>Name</label>
<input type="text" placeholder="Enter Name" name="name" required>
</div>
<div>
<label> E-mail </label>
<input type="email" placeholder="Enter email ID" name="email" required>
</div>
<div>
<label> Mobile No. </label>
<input type="text" placeholder="Enter Your Mobile No." name="mobileno" required>
</div>
<div>
<label>Password</label>
<input type="password" placeholder="Enter Password" name="psw" required>
<br>
</div>
<button type="submit" VALUE="SUBMIT"> SUBMIT </button>
</form>
</body>
</html>
輸出:

<select>
我們可以輕鬆地將 required 屬性與 <select> 元素一起使用,如以下語法所示:
<select required>
示例
<html>
<head>
<title> Example of required attribute with select option </title>
<style>
div
{
padding:10px 0;
}
</style>
<head>
<body>
<form>
<label>
Course:
</label>
<select required>
<option value="">None</option>
<option value="BCA">BCA</option>
<option value="BBA">BBA</option>
<option value="B.Tech">B.Tech</option>
<option value="MBA">MBA</option>
<option value="MCA">MCA</option>
<option value="M.Tech">M.Tech</option>
</select>
<button type="submit" VALUE="SUBMIT"> SUBMIT </button>
</form>
</body>
</html>
輸出:

<textarea>
我們還可以輕鬆地將 required 屬性與 <textarea> 元素一起使用,如以下語法所示:
<textarea required>
示例
<html>
<head>
<title> Example of required attribute with textarea </title>
<style>
div
{
padding:10px 0;
}
</style>
<head>
<body>
<form>
Any Comment:
<br>
<textarea cols="80" rows="5" placeholder="Enter a comment" value="address" required>
</textarea>
<button type="submit" VALUE="SUBMIT"> SUBMIT </button>
</form>
</body>
</html>
輸出:

瀏覽器支持
Element | ![]() | ![]() | ![]() | ![]() | ![]() |
<required> | Yes | Yes | Yes | Yes | Yes |
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注:本文由純淨天空篩選整理自 HTML Required Attribute。非經特殊聲明,原始代碼版權歸原作者所有,本譯文未經允許或授權,請勿轉載或複製。