1 chap5_forms_and_html_helpers

jason-zhu edited this page 2023-10-22 12:15:53 +11:00

Table of Contents

• Chapter 5: Forms and HTML Helpers
• Using Forms
• The Action and the Method
• To GET or To POST

Chapter 5: Forms and HTML Helpers

Topic in this chapter: (May not be summarized)

• Understanding forms
• How to make HTML helpers work for you
• Editing and inputting helpers
• Displaying and rendering helpers

HTML helpers requires coordination between a view and the runtim.

Using Forms

Before understanding HTML helper, first get familiar with HTML form tag.

The Action and the Method

A form is a container for one or more different input elements, e.g.:

• buttons
• checkboxs
• text inputs, etc.

How form submit user entered information to server:

• through action and method attributes of a form tag
• action attribute tell browser where to send information, hence normally contains URL (relative or absolute)
• method attribute tell browser use GET (default) or POST requests.
• When a user submits a form using an HTTP GET request, the browser takes the input names and values inside the form and puts them in query string.

e.g. HTML form tag transform to URL

<form action="http://www.bing.com/search" method="get">
    <input name="q" type="text" />
    <input type="submit" value="Search!">
</form>

to http://www.bing.com/search?q=love

Details of HTML form is available in w3schools

To GET or To POST

Difference btw GET and POST:

• GET request: browser place input values into query string
• POST request: browser place input values inside the body of the HTTP request instead.

Web app generally use GET requests for reads and POST requests for writes.