Design And Implementation Of COM WebGIS Based On Spatial Index Of Dynamic Hash

The fast development of computer and internet brings broad development and great challenge for traditional Geographic Information System.COM GIS, OPEN GIS and Web GIS and so on the emerging technology arises at the historic moment.Each GIS software factory and the development facility have enlarged this aspect research, and promotes own in abundance GIS product, but the research mentality and the method respectively have each characteristic.This article is precisely under this kind of background, carries on the research discussion to one of GIS development hot spot technology——WebGIS.This article analyzes the WebGIS system from four aspects: Design model,Component Object Model,Web Service and spatial index.(1) The traditional WebGIS realization model mainly has based on the server technology,the client side technology and the server/Client side blending technology. At present the main model which used to structure WebGIS is including traditional B/S three architecture and multi-layer architectures based on the middleware such as CORBA,DCOM,EJB and DotNET and so on.(2) COM technology solved the problems such as high specialized specification,long development cycle,difficulty system integration,which traditional GIS factories had to faced with when developing the GIS application system. It not only simplified the process of developing GIS application system, also provided highly effective,nimble and the function formidable development pattern for WebGIS.(3) Web Service is one kind of brand-new network skeleton technology, which established the distributional system under the heterogenous network environment. WebGIS based on XML Web service has characteristic of distributionally,mutually operate,convenience integration,excellent expansibility, and it is one of WebGIS development tendency. This article facuss on exploring the application of Web...