The AutoSave Form is Used to save Any of the text that the user enters in the TextInput or any other of the supported  Controls such as ComboBox, CheckBox, RadioButton, It uses Ctrl+Y to Redo and Ctrl+Z to Undo, The _undoHistorySize will    be used to control how much of information should we undo or redo. The Default is 5. Also, There is an Optional Validation where the Submit Button or any other button will not be enabled unless all the Validation is correct. We Implement the
IHistoryManagerClient so we can use it to save the states of our text. Lots of comments and view source is enabled.
http://www.sherifabdou.com/FlexAIRExamples/AutoSaveForm/AutoForm.swf