MATLAB Object-Oriented Programming

Modify the Save and Load Process

In this section...

“When to Modify the Save and Load Process” on page 13-16

“How to Modify the Save and Load Process” on page 13-16

“Implementing saveobj and loadobj Methods” on page 13-17

“Additional Considerations” on page 13-17

When to Modify the Save and Load Process

The primary reason for modifying the save and load process is to support backward and

forward compatibility of classes. Consider modifying the save and load process when you:

• Rename a class


• Remove properties


• Define a circular reference of handle objects where initialization order is important


• Must call the constructor with arguments and, therefore, cannot use
  ConstructOnLoad

How to Modify the Save and Load Process

The most versatile technique for modifying the save and load process is to implement

loadobj, and if necessary, saveobj methods for your class. MATLAB executes these

methods when you call save or load on an object of the class.

The save function calls your class saveobj method before performing the save

operation. The save function then saves the value returned by the saveobj method. You

can use saveobj to return a modified object or a struct that contains property values.

load calls your class loadobj method after loading the object. The load function loads

the value returned by the loadobj method into the workspace. A loadobj method can

modify the object being loaded or can reconstruct an object from the data saved by the

class saveobj method.

13 Saving and Loading Objects