文本到十进制转换器工作，但UI没有得到更新

Question

我写了一个字符串到十进制转换器，它工作正常，绑定成功更新，但是，GUI没有得到更新 - 这是针对Windows Phone 8.1 - winrt如果我是对的。

示例：如果我输入＆＃34; 0500＆＃34;它将转换为十进制值，但GUI未更新为500。

此外，转换回来是控制而不是Iconvert中的转换。

我的转换代码：

nvm alias default <version>

请你纠正我或建议我哪里出错了。

Xaml代码：

 Public Class DecimalConverter
            Implements IValueConverter

            Public Function Convert(value As Object, targetType As Type, parameter As Object, language As String) As Object Implements IValueConverter.Convert
                Return value.ToString
            End Function

            Public Function ConvertBack(value As Object, targetType As Type, parameter As Object, language As String) As Object Implements IValueConverter.ConvertBack
                Dim result As Decimal = 0
                Decimal.TryParse(value, result)
                Return result
            End Function
        End Class

输出：

编辑： 绑定类的代码。

xmlns:cn="using:MCPhone81.MCCommonCodes.Converters"
    <Page.Resources>
        <cn:VisibilityConverter x:Name="VisConvert"/>
        <cn:DecimalConverter x:Name="DecConverter"/>
    </Page.Resources>

<TextBox Text="{Binding Obj.Amount, Mode=TwoWay, Converter={StaticResource DecConverter}}" Grid.Row="2" Grid.Column="0" MinWidth="220" InputScope="Number" />

编辑：在UI上绑定数据

Public Class SimpleReceipt
            Inherits BaseClass
            Private _CollectionAmountValue As Decimal
            Property CollectionAmount As Decimal
                Get
                    Return _CollectionAmountValue
                End Get
                Set(value As Decimal)
                    If Not _CollectionAmountValue = value Then
                        _CollectionAmountValue = value
                        NotifyPropertyChanged("CollectionAmount")
                    End If
                End Set
            End Property
End Class
Public Class BaseClass
    Implements ComponentModel.INotifyPropertyChanged

    Public Event PropertyChanged(sender As Object, e As ComponentModel.PropertyChangedEventArgs) Implements ComponentModel.INotifyPropertyChanged.PropertyChanged
    Public Sub NotifyPropertyChanged(ByVal PropertyName As String)
        RaiseEvent PropertyChanged(Me, New ComponentModel.PropertyChangedEventArgs(PropertyName))
    End Sub

End Class