var task1 = Task.Run(() =>
{
this.Dispatcher.Invoke(new Action(() =>
{
textBlockResult.Text = "task run";
}));
});
// 処理呼び出しの優先順位を付けて
//
var task2 = Task.Run(() =>
{
this.Dispatcher.Invoke(DispatcherPriority.Render,
new Action(() =>
{
textBlockResult.Text = "task run";
}));
});