Link to Open New Email Message in Default E-mail Handler in WPF Application

If you want the style to be like a hyperlink, why not just use one directly?

<TextBlock>           
    <Hyperlink NavigateUri="mailto:[email protected]?subject=SubjectExample&amp;body=BodyExample" RequestNavigate="OnNavigate">
        Click here
    </Hyperlink>
</TextBlock>

Then add:

private void OnNavigate(object sender, RequestNavigateEventArgs e)
{
    Process.Start(e.Uri.AbsoluteUri);
    e.Handled = true;
}

You can do this entirely in XAML Use Expression interactions to call the link mentioned above.

First, import the following namespaces:

xmlns:i  = "http://schemas.microsoft.com/expression/2010/interactivity"
xmlns:ei = "http://schemas.microsoft.com/expression/2010/interactions"

Then, use them like the following:

<Label Content="Send Email">
  <i:Interaction.Triggers>
    <i:EventTrigger EventName="MouseLeftButtonUp">
      <ei:LaunchUriOrFileAction Path="mailto:[email protected]" />
    </i:EventTrigger>
  </i:Interaction.Triggers>
</Label>