Question

在我的项目中，我有以下几页：

Mainwindow.xaml

Window1.xaml

User.cs

的App.xaml

我在Name和Age上声明了User.cs和MainWindow.xaml属性我为ObservableCollection做了ListBox。 MainWindow有一个Button Add。当我们点击Add button时。然后显示Window1.xaml表单。其中有两个TextBoxes名称和年龄以及一个按钮（ADD Name）。现在我想点击Add Name button，然后两个文本框中的详细信息都会附加到ObservableCollection上定义的Mainwindow.xaml.cs。

请建议我可以这样做：

public partial class Window1 : Window
{

    public Window1()
    {
        InitializeComponent();
    }

    private void OnInit(object sender, RoutedEventArgs e)
    {
        string textA=textBox1.Text;
        int textB=Convert.ToInt32(textBox2.Text);
        this.DataContext = new User(textA, textB);
    }

    private void button1_Click(object sender, RoutedEventArgs e)
    {
        User user = (User)(this.DataContext);
        new MainWindow().observableCollection.Add(user);
        this.Close();
    }
}

现在我运行了这段代码，我无法获取用户对象中的值。

Answer 1

问题是您没有访问MainWindow CbservableCollection，而是创建了新的MainWindow。

如果此Window1是对话框，则您有几个选项

将MainWindow作为其所有者
将Window1用作对话框并在关闭时获取更改

我个人认为第二种选择是最好的，但这取决于你如何调用Window1

例2：

MainWindow Class

public partial class MainWindow : Window
{
    private ObservableCollection<User> _myList = new ObservableCollection<User>();

    public MainWindow()
    {
        InitializeComponent();
    }

    public ObservableCollection<User> MyCollection
    {
        get { return _myList; }
        set { _myList = value; }
    }

    private void button1_Click_1(object sender, RoutedEventArgs e)
    {
        var dialog = new Window1();
        if (dialog.ShowDialog() == true)
        {
            MyCollection.Add(dialog.NewUser);
        }
    }
}

MainWindow xaml

<Window x:Class="WpfApplication8.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="233" Width="405" Name="UI">
    <Grid DataContext="{Binding ElementName=UI}" >
        <ListBox ItemsSource="{Binding MyCollection}" DisplayMemberPath="TextA"  Margin="0,0,0,47" />
        <Button Content="Add" Height="23" HorizontalAlignment="Left" Margin="0,0,0,12" Name="button1" VerticalAlignment="Bottom" Width="75" Click="button1_Click_1" />
    </Grid>
</Window>

Window1 xaml

<Window x:Class="WpfApplication8.Window1"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Window1" Height="119" Width="300" Name="UI">
    <StackPanel DataContext="{Binding ElementName=UI}">
        <TextBox Text="{Binding NewUser.TextA}" />
        <TextBox Text="{Binding NewUser.TextB}" />
        <Button Click="button1_Click" HorizontalAlignment="Right" Width="90" Height="30" Content="Add" />
    </StackPanel>
</Window>

Window1代码

public partial class Window1 : Window, INotifyPropertyChanged
{
    private User _newUser = new User();

    public Window1()
    {
        InitializeComponent();
    }

    public User NewUser
    {
        get { return _newUser; }
        set { _newUser = value; NotifyPropertyChanged("NewUser"); }
    }

    private void button1_Click(object sender, RoutedEventArgs e)
    {
        DialogResult = true;
    }

    public event PropertyChangedEventHandler PropertyChanged;
    public void NotifyPropertyChanged(string property)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(property));
        }
    }
}

用户类

public class User : INotifyPropertyChanged
{
    private string _textA;
    private string _textB;

    public string TextA
    {
        get { return _textA; }
        set { _textA = value; NotifyPropertyChanged("TextA"); }
    }

    public string TextB
    {
        get { return _textB; }
        set { _textB = value; NotifyPropertyChanged("TextB"); }
    }

    public event PropertyChangedEventHandler PropertyChanged;
    public void NotifyPropertyChanged(string property)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(property));
        }
    }
}

无法在observablecollection列表框中添加新行？

1 个答案: