HTML Forms and Input
Forms
A form is an area that can contain form elements.
Form elements are elements that allow the user to enter information (like text fields, textarea fields, drop-down menus, radio buttons, checkboxes, etc.) in a form.
A form is defined with the <form> tag.
HTML Code:
<form>
<input>
<input>
</form>
Input
The most used form tag is the <input> tag. The type of input is specified with the type attribute. The most commonly used input types are explained below.
Text Fields
Text fields are used when you want the user to type letters, numbers, etc. in a form.
HTML Code:
<form>
First name:
<input type="text" name="firstname">
<br>
Last name:
<input type="text" name="lastname">
</form>
How it looks in a browser:
First name:
Last name: Note that the form itself is not visible. Also note that in most browsers, the width of the text field is 20 characters by default.
Radio Buttons
Radio Buttons are used when you want the user to select one of a limited number of choices.
HTML Code:
<form>
<input type="radio" name="sex" value="male"> Male
<br>
<input type="radio" name="sex" value="female"> Female
</form>
How it looks in a browser:
Male
Female Note that only one option can be chosen.
Checkboxes
Checkboxes are used when you want the user to select one or more options of a limited number of choices.
HTML Code:
<form>
I have a bike:
<input type="checkbox" name="vehicle" value="Bike">
<br>
I have a car:
<input type="checkbox" name="vehicle" value="Car">
<br>
I have an airplane:
<input type="checkbox" name="vehicle" value="Airplane">
</form>
How it looks in a browser:
I have a bike:
I have a car:
I have an airplane:
The Form's Action Attribute and the Submit Button
When the user clicks on the "Submit" button, the content of the form is sent to another file. The form's action attribute defines the name of the file to send the content to. The file defined in the action attribute usually does something with the received input.
HTML Code:
<form name="input" action="html_form_action.asp"
method="get">
Username:
<input type="text" name="user">
<input type="submit" value="Submit">
</form>
How it looks in a browser:
Username: If you type some characters in the text field above, and click the "Submit" button, you will send your input to a page called "html_form_action.asp". That page will show you the received input.