The intermittency of renewable energy generation, variability of load demand, and stochasticity of market price bring about direct challenges to optimal energy management of microgrids. To cope with these different forms of operation uncertainties, an imitation learning based real-time decision-making solution for microgrid economic dispatch is proposed. In this solution, the optimal dispatch trajectories obtained by solving the optimal problem using historical deterministic operation patterns are demonstrated as the expert samples for imitation learning. To improve the generalization performance of imitation learning and the expressive ability of uncertain variables, a hybrid model combining the unsupervised and supervised learning is utilized. The denoising autoencoder based unsupervised learning model is adopted to enhance the feature extraction of operation patterns. Furthermore, the long short-term memory network based supervised learning model is used to efficiently characterize the mapping between the input space composed of the extracted operation patterns and system state variables and the output space composed of the optimal dispatch trajectories. The numerical simulation results demonstrate that under various operation uncertainties, the operation cost achieved by the proposed solution is close to the minimum theoretical value. Compared with the traditional model predictive control method and basic clone imitation learning method, the operation cost of the proposed solution is reduced by 6.3% and 2.8%, respectively, over a test period of three months.