HTML select required attribute

Online Example

HTML form with a required dropdown list:

<form action="action_page.php">
<select name="lan" required>
　　<option value="PHP">PHP</option>/option>
　　<option value="Python">Python</option>/option>
　　<option value="C#">C#</option>
　　<option value="Golang">Golang</option>
</select>
<input type="submit">
</form>

Browser Compatibility

IEFirefoxOperaChromeSafari

Almost all mainstream browsers do not support the required attribute.

Definition and Usage

The required attribute is a boolean attribute.

The required attribute specifies that a user must select a value before submitting the form.

HTML 4.01 with HTML5differences

The required attribute is in HTML5 with the newly added attributes.

Differences between HTML and XHTML

In XHTML, attribute abbreviations are prohibited, the required attribute must be defined as <select required="required" />。

Syntax

<select required>