Question

所以我有一个问题。我尝试使用MVVM模式将数据保存到一个人类，我想，这应该很容易 - 我是一个绝对的初学者。我已经有2个视图，2个MainViewModels和2个命令（添加和删除，删除工作正常）。

当我启动我的应用程序时，可以按下添加按钮并打开一个新窗口。我可以在文本框中输入一些数据，如名称，金额和价格。现在我需要一种简单的方法来保存我的Observable Collection中的数据。那我该怎么做呢？

我的想法，点击保存按钮后，一个方法被调用（构造函数），我将数据保存在我的可观察集合中，但我该如何实现这个方法？

MainViewModel

class MainViewModel : BaseViewModel
{
    ObservableCollection<Software> Data;

    Software selected;

    public Software Selected
    {
        get { return selected; }
        set { selected = value; }
    }

    public ObservableCollection<Software> swdata
    {
        get { return Data; }
        set { Data = value; }
    }


    #region ATTRIBUTES
    private double purchaseprice;
    private String name;
    private double salesprice;
    #endregion
    #region CONSTRUCTOR


    public String Name
    {
        get { return selected.Name; }
        set
        {
            selected.Name = value;
        OnPropertyChanged("Name");
        }
    }


    public double Purchaseprice
    {
        get { return selected.PurchasePrice; }
        set
        {
            selected.PurchasePrice = value;
        OnPropertyChanged("Purchaseprice");
        }
    }


    public double Salesprice
    {
        get { return selected.SalesPrice; }
        set
        {
            selected.SalesPrice = value;
        OnPropertyChanged("Salesprice");
        }
    }

    #endregion

    public MainViewModel()
    {
        Data = LoadSample();
    }

    public ICommand AddItem { get; set; }
    public ICommand DeleteItem { get; set; }


    public ObservableCollection<Software> LoadSample()
    {
        this.AddItem = new AddCommand(this);
        this.DeleteItem = new DeleteCommand(this);

        if (Data == null)
        {
            Data = new ObservableCollection<Software>();
            Data.Add(new Software("1") { Name = "Adobe Photoshop", SalesPrice = 199, PurchasePrice = 249 });
            Data.Add(new Software("2") { Name = "Adobe Elements", SalesPrice = 179, PurchasePrice = 219 });
            Data.Add(new Software("3") { Name = "Adobe Indesign", SalesPrice = 299, PurchasePrice = 349 });
            Data.Add(new Software("3") { Name = "Microsoft Office", SalesPrice = 199, PurchasePrice = 249 });
            Data.Add(new Software("3") { Name = "SQL Developer ", SalesPrice = 79, PurchasePrice = 129 });
            Data.Add(new Software("3") { Name = "Microsoft Windows 7", SalesPrice = 89, PurchasePrice = 99 });

        }
        return Data;
    }
}

AddCommand

class AddCommand : ICommand
{

    //Call MainViewModel
    #region MVM CALL
    private readonly MainViewModel pMainViewModel;
    #endregion
    #region MVM CONSTRUCTOR
    public AddCommand(MainViewModel xMainViewModel)
    {
        pMainViewModel = xMainViewModel;
    }
    #endregion

    #region CANEXECUTE
    public bool CanExecute(object parameter)
    {
        return (pMainViewModel.Selected != null);
    }
    #endregion

    #region EVENTHANDLER
    public event EventHandler CanExecuteChanged
    {
        add { CommandManager.RequerySuggested += value; }
        remove { CommandManager.RequerySuggested -= value; }
    }


    public void Execute(object parameter)
    {

        var dialog = new AddView()
        {
           // Owner = this,
                DataContext = null
        };

        dialog.ShowDialog();

    }
    #endregion
}

Screenshot

WPF / MVVM将数据保存到类

0 个答案: