HTML Forms
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HTML
Forms
An HTML form is used to collect user input. The user input is
most often sent to a server for processing.
Example
First name:
Last name:
Try it Yourself »
The <form> Element
The HTML <form>
element is used to
create an HTML form for user input:
<form>
.
form elements
.
</form>
The <form>
element is a container for different types of input elements,
such as: text fields, checkboxes, radio
buttons, submit buttons, etc.
All
the different form elements are covered in this chapter:
HTML Form Elements.
The <input> Element
The HTML <input>
element is the most
used form element.
An <input>
element can be displayed in
many ways, depending on the type
attribute.
Here are some examples:
Type
Description
<input type=”text”>
Displays a single-line text input field
<input type=”radio”>
Displays a radio button (for selecting one of many choices)
<input type=”checkbox”>
Displays a checkbox (for selecting zero or more of many choices)
<input type=”submit”>
Displays a submit button (for submitting the form)
<input type=”button”>
Displays a clickable button
All the different input types are covered in this chapter:
HTML Input Types.
Text Fields
The <input type="text">
defines a single-line input field for
text input.
Example
A form with input fields for text:
<form>
<label for=”fname”>First name:</label><br>
<input
type=”text” id=”fname” name=”fname”><br>
<label for=”lname”>Last
name:</label><br>
<input type=”text” id=”lname” name=”lname”>
</form>
Try it Yourself »
This is how the HTML code above will be displayed in a browser:
First name:
Last name:
Note: The form itself is not visible. Also note that the default width
of an input field is 20 characters.
The <label> Element
Notice the use of the <label>
element in the
example above.
The <label>
tag defines a label for many
form elements.
The <label>
element is useful for
screen-reader users, because the screen-reader will read out loud the label when
the user focuses on the input element.
The <label>
element also helps users who have
difficulty clicking on very small regions (such as radio buttons or checkboxes)
– because when the user clicks the text within the <label>
element, it toggles
the radio button/checkbox.
The for
attribute of the <label>
tag should
be equal to the id
attribute of the <input>
element to bind them together.
Radio Buttons
The <input type="radio">
defines a radio button.
Radio buttons let a user select ONE of a limited number of choices.
Example
A form with radio buttons:
<p>Choose your favorite Web language:</p>
<form>
<input type=”radio” id=”html” name=”fav_language”
value=”HTML”>
<label for=”html”>HTML</label><br>
<input
type=”radio” id=”css” name=”fav_language” value=”CSS”>
<label
for=”css”>CSS</label><br>
<input type=”radio” id=”javascript”
name=”fav_language” value=”JavaScript”>
<label for=”javascript”>JavaScript</label>
</form>
Try it Yourself »
This is how the HTML code above will be displayed in a browser:
Choose your favorite Web language:
HTML
CSS
JavaScript
Checkboxes
The <input type="checkbox">
defines a checkbox.
Checkboxes let a user select ZERO or MORE options of a limited number of choices.
Example
A form with checkboxes:
<form>
<input type=”checkbox” id=”vehicle1″ name=”vehicle1″ value=”Bike”>
<label for=”vehicle1″> I have a bike</label><br>
<input
type=”checkbox” id=”vehicle2″ name=”vehicle2″ value=”Car”>
<label for=”vehicle2″>
I have a car</label><br>
<input type=”checkbox”
id=”vehicle3″ name=”vehicle3″
value=”Boat”>
<label for=”vehicle3″> I have a boat</label>
</form>
Try it Yourself »
This is how the HTML code above will be displayed in a browser:
I have a bike
I have a car
I have a boat
The Submit Button
The <input type="submit">
defines a button for submitting the form data to a form-handler.
The form-handler is typically a file on the server with a script for processing
input data.
The form-handler is specified in the form’s action
attribute.
Example
A form with a submit button:
<form action=”/action_page.php”>
<label for=”fname”>First
name:</label><br>
<input type=”text” id=”fname” name=”fname”
value=”John”><br>
<label for=”lname”>Last name:</label><br>
<input type=”text” id=”lname” name=”lname” value=”Doe”><br><br>
<input type=”submit” value=”Submit”>
</form>
Try it Yourself »
This is how the HTML code above will be displayed in a browser:
First name:
Last name:
The Name Attribute for <input>
Notice that each input field must have a name
attribute to be submitted.
If the name
attribute is omitted, the value of the input field will not be sent at all.
Example
This example will not submit the value of the “First name” input field:
<form action=”/action_page.php”>
<label for=”fname”>First
name:</label><br>
<input type=”text” id=”fname” value=”John”><br><br>
<input type=”submit” value=”Submit”>
</form>
Try it Yourself »
HTML Exercises
Test Yourself With Exercises
Exercise:
In the form below, add an input field with the type “button” and the value “OK”.
<form>
<>
</form>
Start the Exercise