CODEWITHSUNDEEP
c#wpfxamldata-bindingstring-formatting
bmt22033
bmt22033

Reputation: 7230

Use StringFormat to add a string to a WPF XAML binding

I have a WPF 4 application that contains a TextBlock which has a one-way binding to an integer value (in this case, a temperature in degrees Celsius). The XAML looks like this:

<TextBlock x:Name="textBlockTemperature">
        <Run Text="{Binding CelsiusTemp, Mode=OneWay}"/></TextBlock>

This works fine for displaying the actual temperature value but I'd like to format this value so it includes °C instead of just the number (30°C instead of just 30). I've been reading about StringFormat and I've seen several generic examples like this:

// format the bound value as a currency
<TextBlock Text="{Binding Amount, StringFormat={}{0:C}}" />

and

// preface the bound value with a string and format it as a currency
<TextBlock Text="{Binding Amount, StringFormat=Amount: {0:C}}"/>

Unfortunately, none of the examples I've seen have appended a string to the bound value as I'm trying to do. I'm sure it's got to be something simple but I'm not having any luck finding it. Can anyone explain to me how to do that?

Upvotes: 161

Views: 288902

Answers (4)

Casper Ehrenborg
Casper Ehrenborg

Reputation: 1539

Please note that using StringFormat property in Bindings only seems to work for "text" properties. Using this for Label.Content will not work

Upvotes: 153

Rajesh Nath
Rajesh Nath

Reputation: 39

In xaml 

<TextBlock Text="{Binding CelsiusTemp}" />

In ViewModel, this way setting the value also works: 

 public string CelsiusTemp
        {
            get { return string.Format("{0}°C", _CelsiusTemp); }
            set
            {
                value = value.Replace("°C", "");
              _CelsiusTemp = value;
            }
        }

Upvotes: -17

denis morozov
denis morozov

Reputation: 6316

Here's an alternative that works well for readability if you have the Binding in the middle of the string or multiple bindings: 

<TextBlock>
  <Run Text="Temperature is "/>
  <Run Text="{Binding CelsiusTemp}"/>
  <Run Text="°C"/>  
</TextBlock>

<!-- displays: 0°C (32°F)-->
<TextBlock>
  <Run Text="{Binding CelsiusTemp}"/>
  <Run Text="°C"/>
  <Run Text=" ("/>
  <Run Text="{Binding Fahrenheit}"/>
  <Run Text="°F)"/>
</TextBlock>

Upvotes: 141

Reed Copsey
Reed Copsey

Reputation: 564323

Your first example is effectively what you need:

<TextBlock Text="{Binding CelsiusTemp, StringFormat={}{0}°C}" />

Upvotes: 312

Related Questions