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copied!<p>Binding in Silverlight requires a Source object or a Dependency object. From that source object you can bind to Properties (hence by definition you are binding to instance members) or Dependency Properties.</p> <p>Since <code>DateTime.Now</code> is a static property you cannot bind to it in Silverlight directly, hence some code is needed. The next best thing is to use code to:-</p> <ul> <li>ensure as much of what you need can be expressed in XAML</li> <li>to do so in an as de-coupled manner as possible.</li> </ul> <p>Hence we can analyse that we need two things.</p> <ol> <li>Expose the static members of DateTime as instance properties of some object</li> <li>Have some way to format the DateTime to a desirable output.</li> </ol> <p>To handle the first item I would create a <code>StaticSurrogate</code> class, where I would create instance properties for the static properties that we need access to:-</p> <pre><code>public class StaticSurrogate { public DateTime Today { get { return DateTime.Today; } } public DateTime Now { get { return DateTime.Now; } } } </code></pre> <p>Now we need a way to format a Date time. A value converter is the right tool for this job, borrowing heavily from this <a href="http://timheuer.com/blog/archive/2008/07/30/format-data-in-silverlight-databinding-valueconverter.aspx" rel="noreferrer">Tim Heuer Blog</a> :-</p> <pre><code>public class FormatConverter : IValueConverter { public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { if (parameter != null) { string formatterString = parameter.ToString(); if (!String.IsNullOrEmpty(formatterString)) { return String.Format(culture, String.Format("{{0:{0}}}", formatterString), value); } } return (value ?? "").ToString(); } public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { throw new NotImplementedException(); } } </code></pre> <p>With these two classes in place we can now do the rest in Xaml, first we need instances of these classes in our resources:-</p> <pre><code><UserControl.Resources> <local:StaticSurrogate x:Key="Static" /> <local:FormatConverter x:Key="Formatter" /> </UserControl.Resources> </code></pre> <p>Now we can wire up the <code>TextBlock</code> :-</p> <pre><code><TextBlock Text="{Binding Today, Source={StaticResource Static}, Converter={StaticResource Formatter}, ConverterParameter='dd MMM yyy'}" /> </code></pre> <p>Note that this approach has the following advantages:-</p> <ul> <li>we do not need to add code to the UserControl on which the TextBlock is placed, nor do we have to fiddle around with any data context.</li> <li>The Static resources could be placed in the App.Resources which would make the creation of the TextBlock entirely independent of having to add anything else to the UserControl.</li> <li>The formatting used to display the date can be independently modified.</li> <li>Access to additional static properties can easily be added to the <code>StaticSurrogate</code> class.</li> </ul>

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