The Designe And Implementation Of A Mapobject Based Special Subject Map Symbol Base

The rapid development of computer and the emergence of digital map and electronic map is motivating Geographic Information System greatly. Because and new methods constant to appear new technology who data gather, make geographical the data of information measured and increase rapidly, How at area information directly perceived through the senses, clear, the image, Abundant representing to the user, become the problem of geographical information system discipline badly in need of solution at present, At geographical information systems soft wares map who achievement show that we need and update most. The expression of the map information depends on showing in various kinds of form map symbols. Among computer system, want and satisfy screen export and show and want satisfied to type exporting, The easy operating natures of the variety and symbolization to the symbol base are expected much. Because designed and need different symbol systems map too special topic, The need in the form of satisfying differently.Component subject symbol who this text introduce design and the system designing and implementation methods of object oriented programming.Use VC + +6 and MapObject of Arc/Info geographical information systems who company produce develop package integrate and develop. Use VC. 0 + +6 and MapObject develop special subject have fast by map symbol base, succinct, apt to integrate the merit used. System have and sew and integrate and arrive a existing one geographical information realize map shows and type exporting by symbolization by systems soft ware. Have users easy to operate, the characteristic convenient to be practical.Article introduce special subject map symbol base research and state of development and special subject map system design and important meaning that realize who symbol cry at present at first; Then, and symbol organize the way and forms the way ensemble architecture the discussion this symbol base the compositions of system; Have explained the organization of the symbol system and the questions of the symbol implementation method and symbolization of special topic especially; Have narrated the index of the symbol which realizes the symbolization and visit way in detail; Having explained some symbols, a symbol, the realization and classificationof the line symbol organize the question. Research and solve the limitation problem that MapObject develops and needs overcoming in the symbol base. Then discussed the realization of the integrated symbol base and question of using in the existing system, With grading and define the level system integrate and test the symbol base system of special topic about the land for backing agricultural. Article develop and use and development trend make brief analysis and look forward to subject topic symbol base at last.