Get the source code: MVVM.cs
MVVM.cs is a collection of Model-View-ViewModel (MVVM) design pattern common classes that can be implemented by any ViewModel (VM). I created this collection into a single file, so whenever I want to develop MVVM-based application (without using MVVM frameworks) in .NET C#, I just need to reference it and inherit the ViewModelBase class into any of my VM classes.
Usage examples
To raise any property change, you may use these following methods:
OnPropertyChanged("YourPropertyName");- Lambda function:
RaisePropertyChanged(() => YourPropertyName);
Example:
using HeiswayiNrird.MVVM.Common; // MVVM.cs
using System;
namespace MVVMExampleApp
{
public class ViewModelExample : ViewModelBase
{
private object _propertyName1;
public object PropertyName1
{
get { return _propertyName1; }
set
{
_propertyName1 = value;
OnPropertyChanged("PropertyName1");
}
}
private object _propertyName2;
public object PropertyName2
{
get { return _propertyName2; }
set
{
_propertyName2 = value;
RaisePropertyChanged(() => PropertyName2); // Use of lambda expression
}
}
}
}
For ICommand property, you may use any of these following classes:
DelegateCommand()RelayCommand()
Example:
using HeiswayiNrird.MVVM.Common; // MVVM.cs
using System.Windows.Input;
using System;
namespace MVVMExampleApp
{
public class ViewModelExample : ViewModelBase
{
// Example 1 : DelegateCommand
private ICommand _commandProperty1;
public ICommand CommandProperty1
{
get
{
if (_commandProperty1 == null)
{
//_commandProperty1 = new DelegateCommand(methodToExecute);
_commandProperty1 = new DelegateCommand(methodToExecute, canExecuteMethodToExecute);
}
return _commandProperty1;
}
}
// Example 2 : DelegateCommand with type
private ICommand _commandProperty2;
public ICommand CommandProperty2
{
get
{
if (_commandProperty2 == null)
{
_commandProperty2 = new DelegateCommand<int>(methodToExecute2);
}
return _commandProperty2;
}
}
// Example 3 : RelayCommand
private ICommand _commandProperty3;
public ICommand CommandProperty3
{
get
{
if (_commandProperty3 == null)
{
_commandProperty3 = new RelayCommand(
param => methodToExecute(),
param => canExecuteMethodToExecute()
);
}
return _commandProperty3;
}
}
// Example 4 : RelayCommand with parameter
private ICommand _commandProperty4;
public ICommand CommandProperty4
{
get
{
if (_commandProperty4 == null)
{
_commandProperty4 = new RelayCommand(
param => methodToExecute2((int)param), // Use with UI control CommandParameter property
param => canExecuteMethodToExecute()
);
}
return _commandProperty4;
}
}
private void methodToExecute2(int param)
{
throw new NotImplementedException();
}
private void methodToExecute()
{
// Logic to execute...
}
private bool canExecuteMethodToExecute()
{
// Put your expression/condition here, return true/false...
return true;
}
}
}