HTML Forms Tag with Example :- Infinity4Education

HTML Forms

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An HTML form is used to collect user input. The user input can then be sent to a server for processing.

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Example

Top of Form

First name:

Last name:

Bottom of Form

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The <form> Element

The HTML <form> element defines a form that is used to collect user input:

<form>
.
form elements
.
</form>

An HTML form contains form elements.

Form elements are different types of input elements, like: text fields, checkboxes, radio buttons, submit buttons, and more.

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The <input> Element

The <input> element is the most important form element.

The <input> element is displayed in several ways, depending on the type attribute.

Here are some examples:

Type	Description
<input type="text">	Defines a single-line text input field
<input type="radio">	Defines a radio button (for selecting one of many choices)
<input type="submit">	Defines a submit button (for submitting the form)

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Text Fields

<input type="text"> defines a single-line input field for text input.

Example

A form with two text input fields:

<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>

This is how it will look like in a browser:

Top of Form

First name:

Last name:

Bottom of Form

Note: The form itself is not visible. Also note that the default width of an input field is 20 characters.

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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 is focused on the input element.

The <label> element also help 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.

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Radio Buttons

<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:

<form>
  <input type="radio" id="male" name="gender" value="male">
  <label for="male">Male</label><br>
  <input type="radio" id="female" name="gender" value="female">
  <label for="female">Female</label><br>
  <input type="radio" id="other" name="gender" value="other">
  <label for="other">Other</label>
</form>

This is how the HTML code above will be displayed in a browser:

 Male
 Female
 Other

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The Submit Button

<input type="submit"> defines a button for submitting the form data to a form-handler.

The form-handler is typically a page 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>

This is how the HTML code above will be displayed in a browser:

Top of Form

First name:

Last name:

Bottom of Form

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The Action Attribute

The action attribute defines the action to be performed when the form is submitted.

Usually, the form data is sent to a page on the server when the user clicks on the submit button.

In the example above, the form data is sent to a page on the server called "/action_page.php". This page contains a server-side script that handles the form data:

<form action="/action_page.php">

If the action attribute is omitted, the action is set to the current page.

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The Target Attribute

The target attribute specifies if the submitted result will open in a new browser tab, a frame, or in the current window.

The default value is "_self" which means the form will be submitted in the current window.

To make the form result open in a new browser tab, use the value "_blank".

Example

Here, the submitted result will open in a new browser tab:

<form action="/action_page.php" target="_blank">

Other legal values are "_parent", "_top", or a name representing the name of an iframe.

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The Method Attribute

The method attribute specifies the HTTP method (GET or POST) to be used when submitting the form data.

Example

Use the GET method when submitting the form:

<form action="/action_page.php" method="get">

or:

Example

Use the POST method when submitting the form:

<form action="/action_page.php" method="post">

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When to Use GET?

The default HTTP method when submitting form data is GET.

However, when GET is used, the form data will be visible in the page's address field:

/action_page.php?firstname=John&lastname=Doe

Notes on GET:

• Appends form-data into the URL in name/value pairs
• The length of a URL is limited (2048 characters)
• Never use GET to send sensitive data! (will be visible in the URL)
• Useful for form submissions where a user wants to bookmark the result
• GET is better for non-secure data, like query strings in Google

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When to Use POST?

Always use POST if the form data contains sensitive or personal information. The POST method does not display the form data in the page address field.

Notes on POST:

• POST has no size limitations, and can be used to send large amounts of data.
• Form submissions with POST cannot be bookmarked

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The Name Attribute

Each input field must have a name attribute to be submitted.

If the name attribute is omitted, the data of that 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>

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Here is the list of all <form> attributes:

Attribute	Description
accept-charset	Specifies the charset used in the submitted form (default: the page charset).
action	Specifies an address (url) where to submit the form (default: the submitting page).
autocomplete	Specifies if the browser should autocomplete the form (default: on).
enctype	Specifies the encoding of the submitted data (default: is url-encoded).
method	Specifies the HTTP method used when submitting the form (default: GET).
name	Specifies a name used to identify the form (for DOM usage: document.forms.name).
novalidate	Specifies that the browser should not validate the form.
target	Specifies the target of the address in the action attribute (default: _self).