我是 WPF 和 MVVM 模式的新手，我嘗試創建一個簡單的 WPF 專案來查詢 I-Shape 鋼型材資料庫并通過 DataGrid 將其顯示給用戶。成功完成后，我現在進入下一部分：讓用戶通過填寫??一組 TextBox 將新的鋼型材添加到 DataGrid。
模型
namespace SectionGuardWPF.MVVM.Model
{
public class IProfileModel : ObservableObject
{
#region Private Fields
public short _recno;
public string _name;
public string _staadName;
public double _ax;
public double _d;
public double _bf;
public double _tf;
public double _tw;
public double _iz;
public double _ix;
public double _ct;
public double _iy;
public double _zx;
public double _zy;
#endregion
#region Public Properties
/// <summary>
/// Properties are given NotifyPropertyChanged method to allow for a change in property to be notified
/// </summary>
public short RECNO
{
get { return _recno; }
set
{
_recno = value;
OnPropertyChanged();
}
}
public string Name
{
get { return _name; }
set
{
_name = value;
OnPropertyChanged();
}
}
...
// Repeated for the other fields
ObservableObject：實作的基類 INotifyPropertyChanged
namespace SectionGuardWPF.Core
{
public class ObservableObject : INotifyPropertyChanged
{
/// <summary>
/// Raised when a property on this object has a new value.
/// </summary>
public event PropertyChangedEventHandler PropertyChanged;
/// <summary>
/// Raises this object's PropertyChanged event.
/// </summary>
protected void OnPropertyChanged([CallerMemberName] string name = null) // If you use the CallerMemberName attribute, calls to the NotifyPropertyChanged method don't have to specify the property name as a string argument
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
}
}
}
中繼命令
namespace SectionGuardWPF.Core
{
class RelayCommand : ICommand
{
private Action<object> _execute;
private Func<object, bool> _canExecute;
public event EventHandler CanExecuteChanged
{
add { CommandManager.RequerySuggested = value; }
remove { CommandManager.RequerySuggested -= value; }
}
public RelayCommand(Action<object> execute, Func<object,bool> canExecute=null)
{
_execute = execute;
_canExecute = canExecute;
}
public bool CanExecute(object parameter)
{
return _canExecute == null || _canExecute(parameter);
}
public void Execute(object parameter)
{
_execute(parameter);
}
}
}
查看模型
namespace SectionGuardWPF.MVVM.ViewModel
{
public class IProfilesViewModel:ObservableObject
{
#region Private Fields
private readonly string _connectionString = //Hidden
private ObservableCollection<IProfileModel> _iProfiles;
private ICommand _getIProfilesCommand;
private ICommand _addNewIProfileCommand;
private IProfileModel _iProfile = new IProfileModel();
#endregion
#region Constructor
public IProfilesViewModel()
{
// Set default Profile Database for the DataGrid upon View instantiation
IProfiles = GetIProfiles();
}
#endregion
#region Public Properties and Commands
/// <summary>
/// Public properties of the IProfilesViewModel Class (used for view binding with IProfilesSubView)
/// </summary>
public ObservableCollection<IProfileModel> IProfiles
{
get { return _iProfiles; }
set
{
_iProfiles = value;
OnPropertyChanged();
}
}
public IProfileModel IProfile
{
get { return _iProfile; }
set
{
_iProfile = value;
OnPropertyChanged();
}
}
public ICommand GetIProfilesCommand
{
get
{
if (_getIProfilesCommand == null)
{
_getIProfilesCommand = new RelayCommand(
param => GetIProfiles()
);
}
return _getIProfilesCommand;
}
}
public ICommand AddNewIProfileCommand
{
get
{
if (_addNewIProfileCommand == null)
{
_addNewIProfileCommand = new RelayCommand(
param => AddNewIProfile()
);
}
return _addNewIProfileCommand;
}
}
#endregion
#region Private Methods
private ObservableCollection<IProfileModel> GetIProfiles()
{
TableDataProvider tableDataProvider = new TableDataProvider(_connectionString);
tableDataProvider.QueryString = "SELECT * FROM [I Shape]";
IEnumerable<IProfileModel> iProfiles = tableDataProvider.Query<IProfileModel>();
ObservableCollection<IProfileModel> iProfileObsvCol = new ObservableCollection<IProfileModel>(iProfiles);
return iProfileObsvCol;
}
private void AddNewIProfile()
{
IProfiles.Add(
new IProfileModel
{
RECNO = IProfile.RECNO,
Name = IProfile.Name,
StaadName = IProfile.StaadName,
AX = IProfile.AX,
D = IProfile.D,
Bf = IProfile.Bf,
Tf = IProfile.Tf,
Tw = IProfile.Tw,
Ix = IProfile.Ix,
Iy = IProfile.Iy,
Iz = IProfile.Iz,
Ct = IProfile.Ct,
Zx = IProfile.Zx,
Zy = IProfile.Zy
}
);
}
#endregion
}
}
看法
<UserControl x:Class="SectionGuardWPF.MVVM.View.IProfilesSubView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:SectionGuardWPF.MVVM.View"
xmlns:viewModel= "clr-namespace:SectionGuardWPF.MVVM.ViewModel"
xmlns:view="clr-namespace:SectionGuardWPF.MVVM.View"
mc:Ignorable="d"
d:DesignHeight="580" d:DesignWidth="1300">
<UserControl.DataContext>
<viewModel:IProfilesViewModel/>
</UserControl.DataContext>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="620"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<DataGrid x:Name="ProfilesDataGrid"
x:FieldModifier="public"
ItemsSource="{Binding IProfiles, Mode=TwoWay}">
</DataGrid>
<Border Grid.Column="1"
CornerRadius="20"
Background ="White"
Margin="10">
<Grid Margin="10">
<Grid.RowDefinitions>
<RowDefinition Height="50"/>
<RowDefinition/>
<RowDefinition Height="150"/>
</Grid.RowDefinitions>
<TextBlock Text="I-Profiles Data Viewer"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="Black"
FontSize="22"/>
<Grid Grid.Row="1">
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<TextBlock Text="RECNO"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="0"
Grid.Row="0"
FontSize="14"/>
<TextBox x:Name="RECNOTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="0"
Grid.Row="0"
Text="{Binding IProfile.RECNO, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Name"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="0"
Grid.Row="1"
FontSize="14"/>
<TextBox x:Name="NameTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="0"
Grid.Row="1"
Text="{Binding IProfile.Name, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="StaadName"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="0"
Grid.Row="2"
FontSize="14"/>
<TextBox x:Name="StaadNameTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="0"
Grid.Row="2"
Text="{Binding IProfile.StaadName, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="AX"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="0"
Grid.Row="3"
FontSize="18"/>
<TextBox x:Name="AXTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="0"
Grid.Row="3"
Text="{Binding IProfile.AX, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="D"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="0"
Grid.Row="4"
FontSize="18"/>
<TextBox x:Name="DTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="0"
Grid.Row="4"
Text="{Binding IProfile.D, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Bf"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="0"
Grid.Row="5"
FontSize="18"/>
<TextBox x:Name="BfTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="0"
Grid.Row="5"
Text="{Binding IProfile.Bf, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Tf"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="0"
Grid.Row="6"
FontSize="18"/>
<TextBox x:Name="TfTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="0"
Grid.Row="6"
Text="{Binding IProfile.Tf, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Tw"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="1"
Grid.Row="0"
FontSize="18"/>
<TextBox x:Name="TwTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="1"
Grid.Row="0"
Text="{Binding IProfile.Tw, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Ix"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="1"
Grid.Row="1"
FontSize="18"/>
<TextBox x:Name="IxTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="1"
Grid.Row="1"
Text="{Binding IProfile.Ix, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Iy"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="1"
Grid.Row="2"
FontSize="18"/>
<TextBox x:Name="IyTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="1"
Grid.Row="2"
Text="{Binding IProfile.Iy, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Iz"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="1"
Grid.Row="3"
FontSize="18"/>
<TextBox x:Name="IzTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="1"
Grid.Row="3"
Text="{Binding IProfile.Iz, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Ct"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="1"
Grid.Row="4"
FontSize="18"/>
<TextBox x:Name="CtTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="1"
Grid.Row="4"
Text="{Binding IProfile.Ct, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Zx"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="1"
Grid.Row="5"
FontSize="18"/>
<TextBox x:Name="ZxTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="1"
Grid.Row="5"
Text="{Binding IProfile.Zx, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
<TextBlock Text="Zy"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="20,0,0,0"
Foreground="#1A80FA"
Grid.Column="1"
Grid.Row="6"
FontSize="18"/>
<TextBox x:Name="ZyTextBox"
Margin="0,0,20,0"
VerticalAlignment="Center"
HorizontalAlignment="Right"
Style="{StaticResource ParameterTextbox}"
Grid.Column="1"
Grid.Row="6"
Text="{Binding IProfile.Zy, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"/>
</Grid>
<StackPanel Grid.Row="2"
Orientation="Horizontal">
<Button x:Name="AddButton"
Style="{StaticResource AddButton}"
Content="Add"
Background="#28C941"
Height="50"
Width="150"
Margin="85,0,0,0"
Command="{Binding AddNewIProfileCommand}"/>
<Button x:Name="EditButton"
Style="{StaticResource AddButton}"
Content="Edit"
Background="#FFBD2E"
Height="50"
Width="150"
Margin="20,0,0,0"/>
<Button x:Name="DeleteButton"
Style="{StaticResource AddButton}"
Content="Delete"
Background="#FF6059"
Height="50"
Width="150"
Margin="20,0,0,0"/>
</StackPanel>
</Grid>
</Border>
</Grid>
</UserControl>
我的 Model 類是一個名為 的類，IProfileModel它表示 I-Shape Profiles，我已經制作了它，以便它從ObservableObject該類繼承，以便它可以使用 NotifyPropertyChanged 方法，并且我已經制作了 Model 類的屬性已經實作了OnPropertyChanged()Method .
In my View, I have bound the source of the DataGrid to the IProfiles which is an ObservableCollection that stores instances of the IProfileModel. Each TextBox corresponds to one property of the IProfileModel class, thus the Text property of each TextBox is bound to its respective nested property of the IProfile property of the ViewModel. The "Add" Button is bound to the respective ICommand in the ViewModel called the AddNewIProfileCommand
In my ViewModel, I have added the IProfileModel as one of its properties using the name IProfile, the TextBox.Text properties are bound to the nested properties of the IProfile as shown in the XAML of the View. As for the AddNewIProfileCommand, I have made so that it corresponds to a private method called the AddNewIProfile() which will add a new IProfileModel object whose properties will refer to the nested properties of the IProfile property that is bound to the TextBoxes.
Edit:
I want to add that the AddNewIProfile() will add the new IProfileModel object to the IProfiles which is bound to the DataGrid
My main issue is that whenever I modified the TextBoxes and then clicked on the Button to add the profiles to the DataGrid, the newly added entry to the DataGrid is always a IProfileModel with empty property values (all string properties of the IProfileModel are null and all numerical type properties are 0). It seems like modifying the TextBoxes does not change the nested properties of the IProfile even though I have set the UpdateSourceTrigger to PropertyChanged and the Mode to Two Way and the IProfile itself is of the IProfileModel class which has inherited from the ObservableObject class.
Lastly, I know that my question is quite similar to this 
Edit: The ParameterTextbox Style which was the cause of the error as pointed out by Cédric Moers in the comments:
<Style TargetType="{x:Type TextBox}"
x:Key="ParameterTextbox">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<Border CornerRadius="5"
Background="White"
Width="180"
Height="35"
BorderThickness="3"
BorderBrush="#EAEAEA">
<Grid>
<Rectangle StrokeThickness="1"/>
<TextBox Margin="1"
Text="{TemplateBinding Text}"
BorderThickness="0"
Background="Transparent"
VerticalContentAlignment="Center"
Padding="5"
Foreground="Black"
x:Name="SearchBox"/>
</Grid>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
uj5u.com熱心網友回復：
我試圖復制你的問題，但我不得不洗掉樣式，因為你沒有提供它們。它在我身邊有效，所以問題可能出在風格上？
請洗掉文本框（ParameterTextbox）的樣式，然后看看它是否有效。如果你能給我提供樣式的源代碼，我可以看一下。也許您正在覆寫 text 屬性。
轉載請註明出處，本文鏈接：https://www.uj5u.com/qukuanlian/407880.html
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