1. A computing device for creating an eForm with business logic, comprising: a processor: a parser for parsing a source eForm to extract attributes of items on the source eForm; an item recognition unit for recognizing interactive items in the source eForm according to attributes of the items extracted by the parser; a business logic recognition unit for recognizing business logic in the source eForm according to the attributes of the items; an object eForm generator for generating an object eForm containing the recognized interactive items and business logic; a fine adjustment unit for modifying incorrectly recognized interactive items and business logic in the object eForm or adding omitted interactive items and business logic to the object; and a trainer which receives the object eForm generated by the object eForm generator and the finely-adjusted object eForm as inputs, compares the difference between the object eForm and the finely-adjusted object eForm at corresponding locations, and revises one or more of the item recognition rules, the simple unit recognition rules, the compound unit recognition rules and the business logic recognition rules as a function of the comparison, wherein the business logic recognition unit further comprises: a simple unit recognizer which groups the items into a plurality of simple units according to the attributes of the items on the basis of simple unit recognition rules; a compound unit recognizer which recognizes one or more compound units according to the types of the simple units and the location relationship among the simple units on the basis of compound unit recognition rules; and a business logic recognizer which detects business logic in the source eForm according to the types, locations and contents of the simple units and the compound units on the basis of business logic recognition rules, the item recognition unit further comprises a plurality of item recognizers, each of which recognizes one or more kinds of interactive items according to an associated item recognition rule.