HTML has the required attribute to accomplish this. If you set any input to be required, modern browsers won’t let you submit the form if those fields are empty.
<input type="text" name="username" required="required" pattern="[A-Za-z0-9]{1,20}">
HTML has the required attribute to accomplish this. If you set any input to be required, modern browsers won’t let you submit the form if those fields are empty.
<input type="text" name="username" required="required" pattern="[A-Za-z0-9]{1,20}">