ABAP-SD enhanced sales price control

Development Requirement: the reserve price of the Order is controlled. when the price is lower than the reserve price, the operator is prompted not to save the order.
First, set a pricing routine in the pricing process, such as: 901/902

Edit the 901 pricing routine. If the price is lower than the base price, the system prompts by warning and saves the current order row to the memory.

Export Enhancement before saving the order, take out the order line with incorrect price, and prompt in error mode, do not allow saving the order, adjust the price above the reserve price to save.