Django CRUD and Forms

Overview

An HTML Form is a group of one or more fields/widgets on a web page, which can be used to collect information from users for submission to a server. Forms are a flexible mechanism for collecting user input because there are suitable widgets for entering many different types of data, including text boxes, checkboxes, radio buttons, date pickers and so on. Forms are also a relatively secure way of sharing data with the server, as they allow us to send data in POST requests with cross-site request forgery protection.

Things Django Form handling does:

• Display the default form the first time it is requested by the user.
  • The form may contain blank fields (e.g. if you’re creating a new record), or it may be pre-populated with initial values (e.g. if you are changing a record, or have useful default initial values).
  • The form is referred to as unbound at this point, because it isn’t associated with any user-entered data (though it may have initial values).
• Receive data from a submit request and bind it to the form.
  • Binding data to the form means that the user-entered data and any errors are available when we need to redisplay the form.
• Clean and validate the data.
• Cleaning the data performs
  • sanitization of the input (e.g. removing invalid characters that might be used to send malicious content to the server) and converts them into consistent Python types.
  • Validation checks that the values are appropriate for the field (e.g. are in the right date range, aren’t too short or too long, etc.)
• If any data is invalid, re-display the form, this time with any user populated values and error messages for the problem fields.
• If all data is valid, perform required actions.
• Once all actions are complete, redirect the user to another page.