Abstract

Undo / Redo library for WPF+MVVM

How to use

Basic

var controller = new OperationController();
var person = new Person() { Name = "Venus" };
var people = new List<Person>();

//  record & execite property setting.
controller.ExecuteSetProperty(person, person => person.Name, "New Name");

// record & execite class-variable setting.
controller.ExecuteSetStaticProperty(typeof(Person), nameof(Person.StaticValue), "ika");

// record & execite list changing.
controller.ExecuteAdd(people, new Person());
controller.ExecuteRemoveAt(people, 0);

controller.Undo();

controller.Redo();

Grouping

You can group multiple changed with OperationController.BeginRecord. In the example below, Name and Age change are grouped. Calling Undo undoes the changes to Name and Age.

var controller = new OperationController();
var person = new Person() { Name = "Venus", Age=13 };

using (controller.BeginRecord())
{
    controller.ExecuteSetProperty(person, nameof(Person.Name), "Changed");
    controller.ExecuteSetProperty(person, nameof(Person.Age), 14);
}

Assert.AreEqual("Changed", person.Name);
Assert.AreEqual(14, person.Age);

controller.Undo();

Assert.AreEqual("Venus", person.Name);
Assert.AreEqual(13, person.Age);

Monitor property changes with NotifyPropertyChanged

Methods listed below monitor property changes with PropertyChanged or CollectionChanged events. When property is changed, record it in OperationController.

• OperationController.BindPropertyChanged
• OperationController.BindListPropertyChanged
• OperationController.BindPropertyChanged2
• OperationController.BindPropertyChanged2Fast

BindPropertyChanged and BindListPropertyChanged methods requires the name of the property to monitor. The object that implements INotifyPropertyChanged2 can be applied to BindPropertyChanged2 and BindPropertyChanged2Fast methods. These methods monitor all properties of the target object. In addition, if the property value implements INotifyPropertyChanged2, properties of this value is monitored.

BindPropertyChanged2 checks the property value. Even if the property type is System.Object, if the value implements INotifyPropertyChanged2, it will be monitored.

BindPropertyChanged2Fast checks the property type only. Even if the property value implements INotifyPropertyChanged2, if the property type is System.Object, it will not be monitored.

var controller = new OperationController();

// the object that implements INotifyPropertyChanged
var person = new Person() { Name = "Venus", Age=13 };
// monitor Name property
controller.BindPropertyChanged(person, nameof(Person.Name), false);
person.Name = "Yammada";
person.Name = "Tanaka";
Assert.AreEqual(2, controller.Undos.Count());
// This is not recorded, because Age is not monitored
person.Age = 15;
Assert.AreEqual(2, controller.Undos.Count());


// the object that implements INotifyPropertyChanged2
var hiperson = new HiPerson() { Name = "Venus", Age=13 };
// All properties of HiPerson is monitord
controller.BindPropertyChanged2(hiperson);
hiperson.Name = "A002";
Assert.AreEqual(3, controller.Undos.Count());
hiperson.Age = 14;
Assert.AreEqual(4, controller.Undos.Count());

Nuget

https://www.nuget.org/packages/TsOpUndo/

Development

IDE: Visual Studio 2019

Build

1. Clone the repository

   git clone https://github.com/whistyun/TsOpUndo.git

2. If you use VisualStudio, open TsOpUndo.git.