Is a diabetic to eat more of complex carbohydrates and reduce simple carbs...What are foods having complex carbs and will it cotrol PP sugar levels.

In general, it is the glycemic index (GI) of the food that makes a significant difference in how the food affects PP glucose levels. The higher the GI the faster and the more it will increase blood glucose level. More complex carbohydrates tend to have lower GI than simple carbohydrates. Understanding GI can be very beneficial in controlling diabetes. A wealth of information about GI is available online.
Fiber is your friend. Complex carbs are generally those with high fiber content. Good choices include fresh fruits, whole grains, starchy vegetables, and beans like pinto beans and black beans. You still need to control the amount of carbs you eat, but these groups will not raise your sugar up as quickly, or as high as simple sugars and whote flour.