Question

我是wpf mvvm的新手。

我需要将数据绑定到viewmodel的view属性。在模型中，我已使用getter和setter声明了所有属性并在viewmodel中声明了属性。

当我尝试绑定值时，它不会更新视图，但值会绑定到属性。控件位于网格内。控件不在网格内绑定。我点击数据网格的行时需要将数据绑定到控件。我正在获取值，但它没有被绑定到控件。

请立即帮助我。

这是我的模特。

public string FirstName{get;set;}        
public string LastName { get; set; }
public DateTime Dob { get; set; }
public int Age { get; set; }
public string Street1 { get; set; }
public string Street2 { get; set; }
public string City { get; set; }
public string State { get; set; }
public string ZipCode { get; set; }
public string PhoneNumber { get; set; }
public string MobileNumber { get; set; }
public string Email { get; set; }
public string Web { get; set;}

这是我的观点模型，

public string Emp_ID;
public string emp_ID {
    get {
        return emp_ID;
    }
    set {
        emp_ID = value;
        OnPropertyChanged("Emp_ID");
    }
}
public string FirstName {
    get {
        return employee.FirstName;
    }
    set {
        employee.FirstName = value;
        OnPropertyChanged("FirstName");
        this.DetailView = new HomeViewModel(value);
    }
}

public string LastName {
    get {
        return employee.LastName;
    }
    set {
        employee.LastName = value;
        OnPropertyChanged("LastName");
    }
}
public DateTime Dob {
    get {
        return employee.Dob;
    }
    set {
        employee.Dob = value;
        OnPropertyChanged("Dob");
        OnPropertyChanged("Age");
    }
}
public int Age {
    get {
        //Birthdate = Convert.ToDateTime(Dob);
        return employee.Age = DateTime.Today.Year - Dob.Year;
    }
    set {
        employee.Age = value;
        OnPropertyChanged("Age");
    }

}
public string Street1 {
    get {
        return employee.Street1;
    }
    set {
        employee.Street1 = value;
        OnPropertyChanged("Street1");
    }
}
public string Street2 {
    get {
        return employee.Street2;
    }
    set {
        employee.Street2 = value;
        OnPropertyChanged("Street2");
    }
}
public string City {
    get {
        return employee.City;
    }
    set {
        employee.City = value;
        OnPropertyChanged("City");
    }
}
public string State {
    get {
        return employee.State;
    }
    set {
        employee.State = value;
        OnPropertyChanged("State");
    }
}
public string ZipCode {
    get {
        return employee.ZipCode;
    }
    set {
        employee.ZipCode = value;
        OnPropertyChanged("ZipCode");
    }
}
public string PhoneNumber {
    get {
        return employee.PhoneNumber;
    }
    set {
        employee.PhoneNumber = value;
        OnPropertyChanged("PhoneNumber");
    }
}
public string MobileNumber {
    get {
        return employee.MobileNumber;
    }
    set {
        employee.MobileNumber = value;
        OnPropertyChanged("MobileNumber");
    }
}
public string Email {
    get {
        return employee.Email;
    }
    set {
        employee.Email = value;
        OnPropertyChanged("Email");
    }
}
public string Web {
    get {
        return employee.Web;
    }
    set {
        employee.Web = value;
        OnPropertyChanged("Web");
    }
}

这是viewmodel
中的绑定代码

public ICommand SelectEmployeeCommand {
    get {
        return selectEmployeeCommand;
    }
    set {
        selectEmployeeCommand = value;
    }
}
private void selectEmployeeDetails() {
    EmployeeViewModel employeeView = new EmployeeViewModel();
    try {
        sqlConnection = new SqlConnection(Connection.connectionstring);
        sqlConnection.Open();
        selectCommand = new SqlCommand(AppConstants.StoredProcedures.GetDataProcedure, sqlConnection);
        selectCommand.CommandType = CommandType.StoredProcedure;
        selectCommand.Parameters.Add(AppConstants.Parameters.Emp_ID, SqlDbType.Int).Value = SelectedEmployee.Row.ItemArray[0];


        sqlAdapter = new SqlDataAdapter(selectCommand);
        sqlDataSet = new DataSet();
        sqlAdapter.Fill(sqlDataSet);
        employeeView.FirstName = sqlDataSet.Tables[0].Rows[0][1].ToString();
        employeeView.LastName = sqlDataSet.Tables[0].Rows[0][2].ToString();
        employeeView.Dob = Convert.ToDateTime(sqlDataSet.Tables[0].Rows[0][3].ToString());
        employeeView.Age = Convert.ToInt32(sqlDataSet.Tables[0].Rows[0][4].ToString());
        employeeView.Street1 = sqlDataSet.Tables[0].Rows[0][5].ToString();
        employeeView.Street2 = sqlDataSet.Tables[0].Rows[0][6].ToString();
        employeeView.City = sqlDataSet.Tables[0].Rows[0][7].ToString();
        employeeView.State = sqlDataSet.Tables[0].Rows[0][8].ToString();
        employeeView.ZipCode = sqlDataSet.Tables[0].Rows[0][9].ToString();
        employeeView.PhoneNumber = sqlDataSet.Tables[0].Rows[0][10].ToString();
        employeeView.MobileNumber = sqlDataSet.Tables[0].Rows[0][11].ToString();
        employeeView.Email = sqlDataSet.Tables[0].Rows[0][12].ToString();
        employeeView.Web = sqlDataSet.Tables[0].Rows[0][13].ToString();
    } catch (Exception ex) {
        throw ex;
    }
}

这是我对视图的完整xaml

<Window x:Class="EmployeeRegistration.Home" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras.WPF4" xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity" xmlns:View="clr-namespace:EmployeeRegistration" Title="Home" Height="595" Width="1096">
    <Window.DataContext>
        <View:EmployeeViewModel></View:EmployeeViewModel>
    </Window.DataContext>
    <i:Interaction.Triggers>
        <i:EventTrigger EventName="Loaded">
            <cmd:EventToCommand Command="{Binding GetEmployeeCommand}" />
        </i:EventTrigger>
    </i:Interaction.Triggers>
    <Window.Resources>
        <Style TargetType="Control" x:Key="myErrorTemplate">
            <Setter Property="Validation.ErrorTemplate"><Setter.Value><ControlTemplate><Border BorderBrush="Red" BorderThickness="1" CornerRadius="2.75" Grid.Column="0"><AdornedElementPlaceholder Name="MyControl" Grid.Column="0"/></Border></ControlTemplate></Setter.Value></Setter><Style.Triggers><Trigger Property="Validation.HasError" Value="true"><Setter Property="ToolTip" Value="{Binding RelativeSource={x:Static RelativeSource.Self},
 Path=(Validation.Errors)[0].ErrorContent
            }

            "/>
 </Trigger></Style.Triggers>
        </Style>
        <Style TargetType="TextBox" BasedOn="{StaticResource myErrorTemplate}" />
    </Window.Resources>
    <Grid Height="984" Width="1073">
        <Grid.RowDefinitions>
            <RowDefinition Height="65"></RowDefinition>
            <RowDefinition Height="36"></RowDefinition>
            <RowDefinition Height="35" />
            <RowDefinition Height="44"></RowDefinition>
            <RowDefinition Height="45" />
            <RowDefinition Height="49" />
            <RowDefinition Height="56" />
            <RowDefinition Height="43" />
            <RowDefinition Height="40" />
            <RowDefinition Height="37"></RowDefinition>
            <RowDefinition Height="39*" />
            <RowDefinition Height="42*" />
            <RowDefinition Height="453*" />
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="538"></ColumnDefinition>
            <ColumnDefinition Width="121" />
            <ColumnDefinition Width="149" />
            <ColumnDefinition Width="110" />
            <ColumnDefinition Width="182" />
        </Grid.ColumnDefinitions>

        <Label Name="lblEmployeeDetails" Content="EMPLOYEE DETAILS" FontFamily="Calibri" FontSize="26" HorizontalAlignment="Center" Margin="117,12,125,6" Width="296"></Label>

        <Label Name="lblHeading" Grid.Column="1" Content="UPDATE EMPLOYEE DETAILS" FontFamily="Calibri" FontSize="26" VerticalAlignment="Center" HorizontalAlignment="Center" Height="44" Width="486" Margin="49,10,27,10" Grid.ColumnSpan="4">
            </Label>

        <TextBlock Margin="0,-2,53,21" HorizontalAlignment="Right" Width="148" Grid.Column="3" Grid.ColumnSpan="2">
            <Button Name="btnNewEmployee" Command="{Binding NewEmployeeCommand}" Content="New Employee Registration" FontFamily="Calibri" Background="#FF2693A7" Foreground="White" />
        </TextBlock>
        <Label Name="lblEnterName" Grid.Row="1" Content="Enter Employee Name:" FontFamily="Calibri" FontSize="16" Margin="0,8,12,21" Grid.RowSpan="2"></Label>
        <TextBox Name="txtSearch" Text="{Binding Path=FirstName,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Grid.Row="1" Margin="174,18,0,31" HorizontalAlignment="Left" Width="186" Grid.RowSpan="2"></TextBox>
        <Button Name="btnSearch" Command="{Binding SearchEmployeeCommand}" Grid.Row="1" Content="Search" Margin="0,18,61,31" HorizontalAlignment="Right" Width="103" Foreground="White" Background="Black" Grid.RowSpan="2"></Button>

        <DataGrid Grid.Row="3" x:Name="grdEmployee" SelectedItem="{Binding SelectedEmployee, Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" ItemsSource="{Binding EmployeeDatatable, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged, NotifyOnSourceUpdated=True}" AutoGenerateColumns="False" IsReadOnly="True" FontFamily="Calibri" HorizontalAlignment="Center" Margin="5,5,39,0" Width="494" CanUserAddRows="False" Background="#FF20E0BB" AlternatingRowBackground="#FF7CB4AB" Height="405" VerticalAlignment="Top" Grid.RowSpan="10">
            <DataGrid.Columns>
                <DataGridTextColumn Binding="{Binding Emp_id}" Header="Employee ID"></DataGridTextColumn>
                <DataGridTextColumn Binding="{Binding FirstName}" Header="FirstName"></DataGridTextColumn>
                <DataGridTextColumn Binding="{Binding LastName}" Header="LastName"></DataGridTextColumn>
                <DataGridTextColumn Binding="{Binding Age}" Header="Age"></DataGridTextColumn>
                <DataGridTextColumn Binding="{Binding ZipCode}" Header="ZipCode"></DataGridTextColumn>
                <DataGridTextColumn Binding="{Binding PhoneNumber}" Header="PhoneNumber"></DataGridTextColumn>
                <DataGridTextColumn Binding="{Binding MobileNumber}" Header="MobileNumber"></DataGridTextColumn>
                <DataGridTemplateColumn>
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Button Content="Edit" Command="{Binding DataContext.SelectEmployeeCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type DataGrid}}}" CommandParameter="{Binding SelectedEmployee}"></Button>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
            </DataGrid.Columns>
        </DataGrid>

        <Label Content="*" Grid.Row="1" Height="30" HorizontalAlignment="Left" Margin="152,10,0,0" Name="lblReqField" VerticalAlignment="Top" Width="16" Foreground="Red" Grid.RowSpan="2" />
        <Label Name="lblPersonalInfo" Content="PERSONAL INFO" FontFamily="Calibri" FontSize="20" Foreground="#FF1C48D8" Grid.Column="1" Grid.Row="1" Height="36" HorizontalAlignment="Left" VerticalAlignment="Top" Grid.ColumnSpan="2" Width="270" />
        <Label Grid.Column="1" Grid.Row="2" Height="35" HorizontalAlignment="Left" Name="lblFirstName" Content="FirstName" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="80" />
        <TextBox Grid.Column="2" Grid.Row="2" Height="25" HorizontalAlignment="Left" Name="txtFirstName" Text="{Binding employee.FirstName, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Window}},Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" BorderBrush="#FF179EB7" VerticalAlignment="Top" Width="130" Margin="9,4,0,0" />


        <Label Height="35" HorizontalAlignment="Left" Margin="0,9,0,0" Name="lblLastName" Content="LastName" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="80" Grid.Column="1" Grid.Row="3" />
        <TextBox BorderBrush="#FF179EB7" Height="25" HorizontalAlignment="Left" Name="txtLastName" Text="{Binding Path=DataContext.LastName, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Grid}},Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" VerticalAlignment="Top" Width="130" Grid.Column="2" Grid.Row="3" Margin="8,9,0,0" />

        <Label Height="35" HorizontalAlignment="Left" Margin="0,10,0,0" Name="lblDob" Content="DOB" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="56" Grid.Column="1" Grid.Row="4" />
        <DatePicker Grid.Column="2" Grid.Row="4" Name="dtpDob" Text="{Binding DataContext.Dob, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Grid}},Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Height="25" HorizontalAlignment="Left" Margin="9,10,0,0" VerticalAlignment="Top" Width="129" />

        <Label Height="28" HorizontalAlignment="Left" Name="lblAge" Content="Age" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="56" Grid.Column="1" Grid.Row="5" Margin="0,6,0,0" />
        <TextBox Height="25" HorizontalAlignment="Left" Name="txtAge" BorderBrush="#FF179EB7" IsReadOnly="True" Text="{Binding DataContext.Age, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Grid}},Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" VerticalAlignment="Top" Width="129" Grid.Column="2" Grid.Row="5" Margin="9,6,0,0" />


        <Label Height="35" HorizontalAlignment="Left" Margin="0,6,0,0" Name="lblAddressInfo" Content="ADDRESS INFO" FontFamily="Calibri" FontSize="20" VerticalAlignment="Top" Width="270" Grid.Column="1" Grid.Row="6" Grid.ColumnSpan="2" />


        <Label Height="35" HorizontalAlignment="Left" Name="lblStreet1" Content="Street1" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="56" Grid.Column="1" Grid.Row="7" />
        <TextBox Name="txtStreet1" BorderBrush="#FF179EB7" Text="{Binding DataContext.Street1, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Grid}},Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Height="25" HorizontalAlignment="Left" VerticalAlignment="Top" Width="129" Grid.Column="2" Grid.Row="7" Margin="9,8,0,0" />

        <Label Height="35" HorizontalAlignment="Left" Name="lblStreet2" Content="Street2" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="56" Grid.Column="1" Grid.Row="8" />
        <TextBox Name="txtStreet2" BorderBrush="#FF179EB7" Text="{Binding Path=Street2, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Grid}},Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Height="25" HorizontalAlignment="Left" Margin="9,6,0,0" VerticalAlignment="Top" Width="130" Grid.Column="2" Grid.Row="8" />

        <Label Height="35" HorizontalAlignment="Left" Name="lblCity" Content="City" FontFamily="Calibri" FontSize="16" Margin="0,1,0,0" VerticalAlignment="Top" Width="56" Grid.Column="1" Grid.Row="9" />
        <ComboBox Text="{Binding DataContext.City, RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Grid}},Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Name="cmbCity" Width="129" Height="25" BorderBrush="#FF179EB7" Grid.Column="2" Grid.Row="9" HorizontalAlignment="Left" Margin="9,5,0,0" VerticalAlignment="Top">
            <ComboBoxItem Content="Kasargod"></ComboBoxItem>
            <ComboBoxItem Content="Kannur"></ComboBoxItem>
            <ComboBoxItem Content="Thrissur"></ComboBoxItem>
            <ComboBoxItem Content="Ernakulam"></ComboBoxItem>
            <ComboBoxItem Content="Palakkad"></ComboBoxItem>
            <ComboBoxItem Content="Alappuzha"></ComboBoxItem>
            <ComboBoxItem Content="Chennai"></ComboBoxItem>
            <ComboBoxItem Content="WhiteField"></ComboBoxItem>
            <ComboBoxItem Content="Bangalore"></ComboBoxItem>
        </ComboBox>

        <Label Height="35" HorizontalAlignment="Left" Name="lblState" Content="State" FontFamily="Calibri" FontSize="16" Margin="0,4,0,0" VerticalAlignment="Top" Width="56" Grid.Column="1" Grid.Row="10" />
        <ComboBox Height="25" HorizontalAlignment="Left" Margin="9,6,0,0" VerticalAlignment="Top" Width="129" Grid.Column="2" Grid.Row="10" Text="{Binding Path=State, Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Name="cmbState" BorderBrush="#FF179EB7">
            <ComboBoxItem Content="Kerala"></ComboBoxItem>
            <ComboBoxItem Content="Karnataka"></ComboBoxItem>
            <ComboBoxItem Content="TamilNadu"></ComboBoxItem>
            <ComboBoxItem Content="AndhraPradesh"></ComboBoxItem>
            <ComboBoxItem Content="Rajastan"></ComboBoxItem>
        </ComboBox>


        <Label Height="35" HorizontalAlignment="Left" Name="lblZipcode" Content="ZipCode" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="65" Grid.Column="1" Grid.Row="11" Margin="3,5,0,0" />
        <TextBox Name="txtZipcode" BorderBrush="#FF179EB7" Text="{Binding Path=ZipCode,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Height="25" HorizontalAlignment="Left" VerticalAlignment="Top" Width="130" Grid.Column="2" Grid.Row="11" Margin="9,0,0,0" />

        <Label Height="35" HorizontalAlignment="Left" Name="lblContactInfo" Content="CONTACT INFO" FontFamily="Calibri" FontSize="20" VerticalAlignment="Top" Width="165" Grid.Column="3" Grid.Row="6" Grid.ColumnSpan="2" Margin="0,6,0,0" />


        <Label Height="35" HorizontalAlignment="Left" Name="lblPhoneNumber" Content="PhoneNumber" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="110" Grid.Column="3" Grid.Row="7" />
        <TextBox Height="25" Name="txtPhoneNo" BorderBrush="#FF179EB7" Text="{Binding Path=PhoneNumber,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" HorizontalAlignment="Left" Margin="1,0,0,0" VerticalAlignment="Top" Width="129" Grid.Column="4" Grid.Row="7" />



        <Label Height="35" HorizontalAlignment="Left" Name="lblMobileNumber" Content="MobileNumber" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="109" Grid.Column="3" Grid.Row="8" Margin="1,2,0,0" Grid.RowSpan="2" />
        <TextBox Name="txtMobileNo" BorderBrush="#FF179EB7" Text="{Binding Path=MobileNumber,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Height="25" HorizontalAlignment="Left" Margin="1,4,0,0" VerticalAlignment="Top" Width="129" Grid.Column="4" Grid.Row="8" />

        <Label Height="35" HorizontalAlignment="Left" Name="lblEmail" Content="Email" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="56" Grid.Column="3" Grid.Row="9" Margin="0,1,0,0" />
        <TextBox Name="txtEmail" BorderBrush="#FF179EB7" Text="{Binding Path=Email,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Height="25" HorizontalAlignment="Left" Margin="0,5,0,0" VerticalAlignment="Top" Width="129" Grid.Column="4" Grid.Row="9" />

        <Label Height="35" HorizontalAlignment="Left" Name="lblWeb" Content="Web" FontFamily="Calibri" FontSize="16" VerticalAlignment="Top" Width="56" Grid.Column="3" Grid.Row="10" Margin="1,4,0,0" />
        <TextBox Name="txtWeb" BorderBrush="#FF179EB7" Text="{Binding Path=Web,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}" Height="25" HorizontalAlignment="Left" Margin="1,4,0,0" VerticalAlignment="Top" Width="129" Grid.Column="4" Grid.Row="10" />
    </Grid>


</Window>

Answer 1

我不知道你究竟想要绑定到什么，但无论如何，我也没有看到你班上INotfyPropertyChanged interface的实现。您应该在ViewModel中实现它，如下所示：

public class SomeClass : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    // This method is called by the Set accessor of each property. 
    // The CallerMemberName attribute that is applied to the optional propertyName 
    // parameter causes the property name of the caller to be substituted as an argument. 
    private void NotifyPropertyChanged([CallerMemberName] String propertyName = "")
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    }

    private int percent = 0;
    public int Percent 
    {
        get { return percent; }
        set
        {
            if (value != percent)
            {
                percent = value;
                NotifyPropertyChanged();
            }
        }
    }
}

这里的绑定将是直接的

...
<ProgressBar Value="{Binding Percent}" />
...

我希望这会有所帮助。

请注意，您需要上面的.NET-Framework 4.5才能使用CallerMemberName。

Answer 2

问题是您有2个EmployeeViewModel对象。一个是在XAML中创建的，并分配给DataContext和调用selectEmployeeDetails（）时创建的那个。

目前还不清楚为什么要在selectEmployeeDetails（）中创建另一个EmployeeViewModel对象，该对象可能是EmployeeViewModel的成员函数。

您是否只需在此功能中设置当前对象属性？

Answer 3

顺便说一下，

public string Emp_ID;
public string emp_ID
    {
        get
        {
            return emp_ID;
        }
        set
        {
            emp_ID = value;
            OnPropertyChanged("Emp_ID");
        }
    }

这会导致递归调用和设置，将emp_ID改为Emp_ID

将数据从viewmodel绑定到视图

3 个答案: