Delay in the implementation of text change in Statusbar control

I have a function a time consuming operation that is done I want to start and end operations appear to be user (By statusbar control) But when performed function, both text executed at the end of function. (user can not sees "Start Operation ...") What solution do you recommend to me?

    private void btnUpdateDataBase_Click(object sender, RoutedEventArgs e)
    {
        开发者_运维技巧TextBlockStatus.Text = "Start Operation ...";

        //Time consuming operation 

        TextBlockStatus.Text = "End Operation ...";
    }

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you need to move the execution to another thread. Do the following:

1. Show the 'Processing' Message
2. Spawn another thread to perform your calculation
3. When the thread completes processing it should trigger an event in the main thread
4. As a part of the event handler replace the "processing' message with the "Completed' message