How to format text strings as numbers in a TextBox?-CodePudding

I have a textbox bound to a string property, containing numeric values

<TextBox Name="txtInvAmount" Text="{Binding Path=InvAmount,UpdateSourceTrigger=PropertyChanged, StringFormat=\{0:F\}}"/>


Private _invAmount as String
Public Property InvAmount As String
    Get
                _invAmount = _objInvoice.AMOUNT.ToString
        Return _invAmount 
    End Get
    Set(ByVal value As String)
        _invAmount = value
        If IsNumeric(_invAmount) Then
            _objInvoice.AMOUNT = value
        Else
            _objInvoice.AMOUNT = Nothing
        End If
        NotifyPropertyChange("InvAmount")
    End Set
End Property

how can I get my string to be formatted as a number, using "." as thousands separator and "," as decimal separator (eg: "1000" should be formatted as "1.000,00")?

PS: I also tried to set

Public Property InvAmount As Double?

that made text value to be displayed with trailing zeros, but not with thousands separator (ie: "1000" is displayed as "1000,00", but not as "1.000,00")

CodePudding user response：

Why don't you make the InvAmount property type Decimal?
Then you can specify the desired format in the binding in the StringFormat property.

Example:

<StackPanel>
    <FrameworkElement.Resources>
        <sys:Decimal x:Key="numeric">123456789.01</sys:Decimal>
    </FrameworkElement.Resources>
    <TextBlock Text="{Binding Source={StaticResource numeric},
                              StringFormat='0,0.00'}"/>
</StackPanel>

Decimal and place separator signs vary by culture. Culture in WPF is set by Language. The default is "en-us". But you can explicitly set it in any element. It will be applied to it and to its children.
You can also explicitly set the culture in the binding.

<StackPanel Language="de">
    <FrameworkElement.Resources>
        <sys:Decimal x:Key="numeric">123456789.01</sys:Decimal>
    </FrameworkElement.Resources>
    <TextBlock Text="{Binding Source={StaticResource numeric},
                              StringFormat='0,0.00'}"/>
    <TextBlock Text="{Binding Source={StaticResource numeric},
                              StringFormat='0,0.00',
                              ConverterCulture=ru-ru}"/>
</StackPanel>

CodePudding user response：

I converted InvAmount property to Nullable(Of Decimal), and placed resource into my usercontrol

<UserControl x:Name="InvoiceControl"
  ...
  xmlns:sys="clr-namespace:System;assembly=mscorlib"
 >
 <UserControl.Resources>
     <sys:Decimal x:Key="numeric">123456789.01</sys:Decimal>
 </UserControl.Resources>
    <Grid Name="grdInvoice">
       <TextBox Name="txtInvAmount" Text="{Binding Path=InvAmount,UpdateSourceTrigger=LostFocus, Source={StaticResource numeric}, StringFormat='0.0,00'}"/>
   </Grid> 
</UserControl>

Property value is not displayed. If I skip StaticResource from textbox, InvAmount value is displayed. I also tried to move StaticResource definition into <Grid.Resources>, but InvAmount is not being displayed into textBox