Hướng dẫn form trong html w3schools

An HTML form is used to collect user input. The user input is most often sent to a server for processing.

The Element

The HTML element is used to create an HTML form for user input:

.
form elements
.

The

Try it Yourself »

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

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

The Element

Notice the use of the element in the example above.

The tag defines a label for many form elements.

The element is useful for screen-reader users, because the screen-reader will read out loud the label when the user focus on the input element.

The 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 element, it toggles the radio button/checkbox.

The for attribute of the tag should be equal to the id attribute of the element to bind them together.

Radio Buttons

The defines a radio button.

Radio buttons let a user select ONE of a limited number of choices.

Example

A form with radio buttons:

Choose your favorite Web language:

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 defines a checkbox.

Checkboxes let a user select ZERO or MORE options of a limited number of choices.

Example

A form with checkboxes:

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 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:

Try it Yourself »

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

The Name Attribute for

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: 

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".

Start the Exercise