When should AJAX be used?
- Form driven interaction
Use it when there is need to edit the field and submit action.
- Deep hierarchical tree navigation
Multiple levels of hierarchy by navigation.
- Rapid user-user communication
Can be used in message posting application, that creates immediate discussions between people. For example, gmail inbox
- Voting, Yes/No boxes, Ratings submissions.
In places where people can vote/rate an article.
- Filtering and involved data manipulation.
Sorting the fields by date and name, applying a filter.
- Commonly entered text hints / autocompletion.
When entering the same text phrases or predictable text phrases. For example, in gmail for adding the email addresses. Can be used to suggest the text phrases while entering the text in a text box. For example, google autosuggest search.
When shouldn’t AJAX be used?
- Username and Password Logins
- Credit card purchases
- Search
If AJAX are used in search , search engines like google cannot see it.
- Replacing a large amount of text
AJAX should not be used when there is need to replace or save large amount of text to the server.
- Useless widgets.
Eliminate the use of sliders, drag and drops, mouse gestures etc. Slider widget can be used to pick the color and a slider to pick the price point in a store using AJAX is just overkill.