I am traveling to shanghai for 5 months and i would like to find accommodation for all this time.

For so long a stay, you must prefer to rent an apartment instead of staying in a hotel or hostel, right? Well, you can try to rent in the nearby Xinqiao Community or Dongfang Fengdian Community near Dongfang Road. Both of them are secure enough. However, the language may be a problem for you to get a suitble one. If possible, ask your Chinese friends to help you or just turn to an agent.