Which HTML should you use?

You are developing a customer web form that includes the following HTML.

<input id = "txtValue" />

A customer must enter a value in the text box prior to submitting the form.

You need to add validation to the text box control.

Which HTML should you use?
A . <input id="txtValue" type="text" required="required"/>
B . <input id="txtValue" type="text" pattern="[A-Za-z]{3}" />
C . <input id="txtValue" type="required" />
D . <input id="txtValue" type="required" autocomplete="on" />

View Answer

Answer: A

Explanation:

Definition and Usage

The required attribute is a boolean attribute.

When present, it specifies that an input field must be filled out before submitting the form.

Example

An HTML form with a required input field:

<form action="demo_form.asp">

Username: <input type="text" name="usrname" required>

<input type="submit">

</form>

Username: <input type="text" name="usrname" required>

Reference: HTML <input> required Attribute

http://www.w3schools.com/tags/att_input_required.asp