Access XAML Instantiated Object from C#

In my XAML I declare an instance of a class called DataConnection, the instance is named MyConnection.

<Window.Resources>
        <!-- Create an instance of the DataConnection class called MyConnection -->
        <!-- The TimeTracker bit comes from the xmlns above -->
        <TimeTracker:DataConnection x:Key="MyConnection" />
        <!-- Define the method which is invoked to obtain our data -->
        <ObjectDataProvider x:Key="Time" ObjectInstance="{StaticResource ResourceKey=MyConnection}" MethodName="GetTimes" />
        <ObjectDataProvider x:Key="Clie开发者_运维百科nts" ObjectInstance="{StaticResource ResourceKey=MyConnection}" MethodName="GetClients" />
</Window.Resources>

Everything in the XAML part works fine. What I want is to be able to reference my instance of MyConnection from my C# code.

How is that possible?

Call FindResource("MyConnection") (docs). You'll need to cast it to the specific type because resources can be any kind of object.

There is also a TryFindResource method for cases where you're not sure whether the resource will exist or not.

FindResource will search the element's resource dictionary as well as any parent elements' resource dictionaries and the application resources.

Resources["MyConnection"] will search only the resource dictionary of that element.

void Window_Loaded(object sender, RoutedEventArgs args) {
    DataConnection dc1 = this.FindResource("MyConnection") as DataConnection;
    DataConnection dc2 = this.Resources["MyConnection"] as DataConnection;
}

The documentation recommends the first approach for normal resource lookups but provides the second approach for when you are retrieving resources from a "known resource dictionary location ... to avoid the possible performance and scope implications of run-time key lookup." link