‫MVVM و الگوی ViewModel Locator

namespace WpfViewModelLocator.ViewModels
{
    public class MainWindowViewModel
    {
        public string SomeText { set; get; }
        public MainWindowViewModel()
        {
            SomeText = "Data ...";
        }
    }
}

using WpfViewModelLocator.ViewModels;

namespace WpfViewModelLocator.ViewModelLocator
{
    public class ViewModelLocatorBase
    {
        public MainWindowViewModel MainWindowVm
        {
            get { return new MainWindowViewModel(); }
        }
    }
}

<Application x:Class="WpfViewModelLocator.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:vml="clr-namespace:WpfViewModelLocator.ViewModelLocator"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <vml:ViewModelLocatorBase x:Key="ViewModelLocatorBase" />
    </Application.Resources>
</Application>

<Window x:Class="WpfViewModelLocator.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"        
        Title="MainWindow" Height="350" Width="525">
    <Grid DataContext="{Binding Path=MainWindowVm, Source={StaticResource ViewModelLocatorBase}}">
        <TextBlock Text="{Binding SomeText}" VerticalAlignment="Top" Margin="5" />
    </Grid>
</Window>

using System;
using System.Globalization;
using System.Linq;
using System.Windows.Data;

namespace WpfViewModelLocator.ViewModelLocator
{
    public class ViewModelLocatorBaseConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            //مقدار در اینجا همان مشخصات ویوو است
            if (value == null) return null;
            string viewTypeName = value.GetType().Name;

            //قرار داد ما است
            //ViewModel Name = ViewName + "ViewModel"
            string viewModelName = string.Concat(viewTypeName, "ViewModel");

            //یافتن اسمبلی که حاوی ویوو مدل ما است
            var asms = AppDomain.CurrentDomain.GetAssemblies();
            var viewModelAsmName = "WpfViewModelLocator"; //نام پروژه مرتبط
            var viewModelAsm = asms.Where(x => x.FullName.Contains(viewModelAsmName)).First();

            //یافتن این کلاس ویوو مدل مرتبط
            var viewModelType = viewModelAsm.GetTypes().Where(x => x.FullName.Contains(viewModelName)).FirstOrDefault();
            if (viewModelType == null)
                throw new InvalidOperationException(string.Format("Could not find view model '{0}'", viewModelName));

            //وهله سازی خودکار آن
            return Activator.CreateInstance(viewModelType);
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}

<Application x:Class="WpfViewModelLocator.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:vml="clr-namespace:WpfViewModelLocator.ViewModelLocator"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <vml:ViewModelLocatorBaseConverter x:Key="ViewModelLocatorBaseConverter" />
    </Application.Resources>
</Application>

<Window x:Class="WpfViewModelLocator.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"                
        DataContext="{Binding RelativeSource={RelativeSource Self}, 
                              Converter={StaticResource ViewModelLocatorBaseConverter}}"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <TextBlock Text="{Binding SomeText}" VerticalAlignment="Top" Margin="5" />
    </Grid>
</Window>