WPF將引數傳遞給帶有工廠委托的頁面

我不知道如何將引數傳遞到新頁面，我有工廠委托可以幫助我進行依賴注入，但我也想通過 Navigate 服務傳遞引數。

應用程式.xml

private void ConfigureServices(ServiceCollection serviceCollection)
    {
        serviceCollection.AddTransient<Home>();
        serviceCollection.AddSingleton<Func<Home>>(ServiceProvider => ServiceProvider.GetService<Home>);

        serviceCollection.AddTransient<PrinterDetails>();
        serviceCollection.AddSingleton<Func<PrinterDetails>>(ServiceProvider => ServiceProvider.GetService<PrinterDetails>);

        serviceCollection.AddTransient<ProvinceList>();
        serviceCollection.AddSingleton<Func<ProvinceList>>(ServiceProvider => ServiceProvider.GetService<ProvinceList>);

        serviceCollection.AddSingleton(Configuration);
        serviceCollection.AddTransient<ISqlDataAccess, SqlDataAccess>();
        serviceCollection.AddTransient<IProvinceListViewModel, ProvinceListViewModel>();
        
        serviceCollection.AddTransient(typeof(MainWindow));
    }

我使用 NavigationService 從 PrinterDetails 頁面導航到 ProvinceList 頁面（當我單擊 btnProvince_Click() 時）

public partial class PrinterDetails : Page, INotifyPropertyChanged
{
    private Func<ProvinceList> ProvinceListFactory { get; }

    
    public PrinterDetails(Func<ProvinceList> provinceListFactory)
    {
        InitializeComponent();
        DataContext = this;

        PrinterService printerService = new PrinterService();
        cmbPrinterList.ItemsSource = printerService.PrinterList();
        ProvinceListFactory = provinceListFactory;
   
    }


    private void btnProvince_Click(object sender, RoutedEventArgs e)
    {
  
        ProvinceList nextPage = this.ProvinceListFactory.Invoke();
        NavigationService.Navigate(nextPage);
    }
}

我要傳遞引數的ProvinceList頁面

public partial class ProvinceList : Page
{
    private readonly IProvinceListViewModel _provinceListViewModel;

    public ProvinceList(IProvinceListViewModel provinceListViewModel)
    {
        InitializeComponent();
        _provinceListViewModel = provinceListViewModel;
        GetProvinceList();
    }

    private void GetProvinceList()
    {
        //How to get parameter from previous page
    }
}

uj5u.com熱心網友回復：

您可以在ProvinceList. 然后PrinterDetails可以在使用工廠創建實體后設定此屬性：

private void btnProvince_Click(object sender, RoutedEventArgs e)
{
  double parameter = 4.5;
  ProvinceList nextPage = this.ProvinceListFactory.Invoke();
  nextPage.Value = parameter;
  NavigationService.Navigate(nextPage);
}

或者，您可以將此引數添加到的建構式中ProvinceList，然后配置 IoC 容器以注入引數。如果引數是動態結果，您必須將您的工廠配置為接受此引數。注冊接受引數 eg 的工廠委托，該引數Func<IProvinceListViewModel, double, ProvinceList>用于構造型別：

// This example assumes that the constructor of ProvinceList 
// requests two parameters of type IProvinceListViewModel and double
serviceCollection.AddSingleton<Func<double, ProvinceList>>(serviceProvider => doubleParameter => 
{
  IProvinceListViewModel viewModel = serviceProvider.GetService<IProvinceListViewModel>();
  return new ProvinceList(viewModel, doubleParameter);
});

serviceCollection.AddTransient<IProvinceListViewModel, ProvinceListViewModel>();

并使用工廠如下：

public PrinterDetails(Func<double, ProvinceList> provinceListFactory)
{
  InitializeComponent();
  ProvinceListFactory = provinceListFactory;
}

private void btnProvince_Click(object sender, RoutedEventArgs e)
{
  double constructorParameter = 4.5;
  ProvinceList nextPage = this.ProvinceListFactory.Invoke(constructorParameter);
  NavigationService.Navigate(nextPage);
}

回答后續問題：

// This example assumes that the constructor of ProvinceList 
// requests two parameters of type IProvinceListViewModel and double
serviceCollection.AddSingleton<Func<double, ProvinceList>>(serviceProvider => doubleParameter => 
{
  IProvinceListViewModel viewModel = serviceProvider.GetService<IProvinceListViewModel>();
  Func<POPList> popListFactory = serviceProvider.GetService<Func<POPList>>();
  return new ProvinceList(viewModel, doubleParameter, popListFactory);
});

serviceCollection.AddTransient<IProvinceListViewModel, ProvinceListViewModel>();
serviceCollection.AddTransient<POPList>();
serviceCollection.AddSingleton<Func<POPList>>(serviceProvider => serviceProvider.GetService<POPList>);

private void btnProvince_Click(object sender, RoutedEventArgs e)
{
  double constructorParameter = 4.5;
  ProvinceList nextPage = this.ProvinceListFactory.Invoke(constructorParameter);
  NavigationService.Navigate(nextPage);
}

標籤：wpf 依赖注入

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