外文翻譯--asp.net技術(shù)和vb語言

1、<p>　　ASP.NET technology and VB language</p><p>　　ASP.NET is a unified Web development model that includes the services necessary for you to build enterprise-class Web applications with a minimum of cod

2、ing. ASP.NET is part of the .NET Framework, and when coding ASP.NET applications you have access to classes in the .NET Framework. You can code your applications in any language compatible with the common language runtim

3、e (CLR), including Microsoft Visual Basic, C#, JScript .NET, and J#. These languages enable you to develop ASP.NET applications </p><p>　　The ASP.NET page and controls framework is a programming framework th

4、at runs on a Web server to dynamically produce and render ASP.NET Web pages. ASP.NET Web pages can be requested from any browser or client device, and ASP.NET renders markup (such as HTML) to the requesting browser. As a

5、 rule, you can use the same page for multiple browsers, because ASP.NET renders the appropriate markup for the browser making the request. However, you can design your ASP.NET Web page to target a specific brows</p>

6、;<p>　　ASP.NET Web pages are completely object-oriented. Within ASP.NET Web pages you can work with HTML elements using properties, methods, and events. The ASP.NET page framework removes the implementation detail

7、s of the separation of client and server inherent in Web-based applications by presenting a unified model for responding to client events in code that runs at the server. The framework also automatically maintains the st

8、ate of a page and the controls on that page during the page processing lif</p><p>　　The ASP.NET page and controls framework also enables you to encapsulate common UI functionality in easy-to-use, reusable co

9、ntrols. Controls are written once, can be used in many pages, and are integrated into the ASP.NET Web page that they are placed in during rendering. The ASP.NET page and controls framework also provides features to contr

10、ol the overall look and feel of your Web site via themes and skins. You can define themes and skins and then apply them at a page level or at a control level</p><p>　　All ASP.NET code is compiled, which enab

11、les strong typing, performance optimizations, and early binding, among other benefits. Once the code has been compiled, the common language runtime further compiles ASP.NET code to native code, providing improved perform

12、ance. </p><p>　　ASP.NET includes a compiler that will compile all your application components including pages and controls into an assembly that the ASP.NET hosting environment can then use to service user r

13、equests. </p><p>　　In addition to the security features of .NET, ASP.NET provides an advanced security infrastructure for authenticating and authorizing user access as well as performing other security-relat

14、ed tasks. You can authenticate users using Windows authentication supplied by IIS, or you can manage authentication using your own user database using ASP.NET forms authentication and ASP.NET membership. Additionally, yo

15、u can manage the authorization to the capabilities and information of your Web application u</p><p>　　ASP.NET always runs with a particular Windows identity so you can secure your application using Windows c

16、apabilities such as NTFS Access Control Lists (ACLs), database permissions, and so on. </p><p>　　For more information on the identity of ASP.NET,ASP.NET provides intrinsic state management functionality that

17、 enables you to store information between page requests, such as customer information or the contents of a shopping cart. You can save and manage application-specific, session-specific, page-specific, user-specific, and

18、developer-defined information. This information can be independent of any controls on the page. </p><p>　　ASP.NET offers distributed state facilities, which enable you to manage state information across mult

19、iple instances of the same application on one computer or on several computers. </p><p>　　ASP.NET applications use a configuration system that enables you to define configuration settings for your Web server

20、, for a Web site, or for individual applications. You can make configuration settings at the time your ASP.NET applications are deployed and can add or revise configuration settings at any time with minimal impact on ope

21、rational Web applications and servers. ASP.NET configuration settings are stored in XML-based files. Because these XML files are ASCII text files, it is simple to </p><p>　　ASP.NET includes features that ena

22、ble you to monitor health and performance of your ASP.NET application. ASP.NET health monitoring enables reporting of key events that provide information about the health of an application and about error conditions. The

23、se events show a combination of diagnostics and monitoring characteristics and offer a high degree of flexibility in terms of what is logged and how it is logged. ASP.NET supports two groups of performance counters acces

24、sible to your applications</p><p>　　You can debug both managed and unmanaged objects, as well as all languages supported by the common language runtime and script languages. </p><p>　　In additio

25、n, the ASP.NET page framework provides a trace mode that enables you to insert instrumentation messages into your ASP.NET Web pages. </p><p>　　ASP.NET supports XML Web services. An XML Web service is a compo

26、nent containing business functionality that enables applications to exchange information across firewalls using standards like HTTP and XML messaging. XML Web services are not tied to a particular component technology or

27、 object-calling convention. As a result, programs written in any language, using any component model, and running on any operating system can access XML Web services. </p><p>　　ASP.NET includes an extensible

28、 hosting environment that controls the life cycle of an application from when a user first accesses a resource (such as a page) in the application to the point at which the application is shut down. While ASP.NET relies

29、on a Web server (IIS) as an application host, ASP.NET provides much of the hosting functionality itself. The architecture of ASP.NET enables you to respond to application events and create custom HTTP handlers and HTTP m

30、odules. </p><p>　　ASP.NET includes enhanced support for creating designers for Web server controls for use with a visual design tool such as Visual Studio. Designers enable you to build a design-time user in

31、terface for a control, so that developers can configure your control's properties and content in the visual design tool. </p><p>　　Microsoft Visual Basic,( abbreviate VB )as tool the most of applica

32、tion program one of under Windows operating platform. No matter beginner or professional developer, VB has all offered a whole set of tools to them, Development application program that it can be relaxed and convenient.

33、So VB as most computer first-selected the ABC of programming language of beginner.</p><p>　　"Visual" mean method to adopt visual user of development figure interface (GUI), need and write a large n

34、umber of code go and describe interface appearance and position of element seldom, Tow and show controlling part that need corresponding position to get screen can help figure design interface, user of figure,; " Ba

35、sic" means BASIC language, because VB is developed on the basis of already existing BAISC language.</p><p>　　VB is a kind of programming language in common use of Microsoft, It, including VBA of the num

36、erous Windows application software use VB language in Microsoft Excel, Microsoft Accessed., For users to carry on the secondary development; Make web page use more VBScript script language sub collection of VB too at pre

37、sent.</p><p>　　Utilize data of VB visit characteristic user can establish the data base to most data base forms including Microsoft SQL Server and other enterprises data base With the application program of

38、front, and adjustable service end part. Utilize ActiveX(TM) technology, VB can use word processor, electronic data list he Windows function that application program offers extremely, Excel of Microsoft,, Word of Microsof

39、t,, Even can use by VB specialty edition or enterprise application program and target th</p><p>　　Section 1 integrated development environments</p><p>　　Integrated environment of VB call IDE, ma

40、de up of a lot of parts , include title board, menu fence, tool fence, controlling part case, And window body window, engineering management device window, attribute window, code window and window body overall arrangemen

41、t window body overall arrangement, etc. of designing etc.. Have covered all functions, such as design which develops the application program, editting, compiling and debugging, etc..</p><p>　　In VB, the appl

42、ication program calls the project too. When start VB and open a new project for the first time, can see and pursue integrated development environment interface that show.</p><p>　　VB come and organize develo

43、pment of application program through project, use project come and manage and form files of application program. One project uses the environment to make up by several window bodies, standard module generally. The system

44、 manages project through the project menu, for instance add the window body, quote . System allow turn on and manage a lot of projects besides. </p><p>　　Section 2 Visual Basic language brief introductions&l

45、t;/p><p>　　Basic use and do the elementary high-level language that used often most. Its full name is Beginner' s All-purpose Symbolic Instruction Code, abbreviate as BASIC. As its name suggests, Basic one

46、specially for language that beginner design, because it easy to learn easy to know, So the body is popular. Early Basic language to belong to and solve translating type, so can carry out line by line , So it can see the

47、result carried out at once , this is a very convenient design for beginner. But it ha</p><p>　　Section 3 Language</p><p>　　The language is the basic composition, which forms VB procedure. VB has

48、 stipulated the form of sentences and function. Grammar:The sentence defines incantations [Sentence body].Sentence define agree with and used in fixed function of sentence, sentence body appoint concrete content or want

49、concrete operation that carry out of sentence. All set of sentence VB language, carry on with VB sentence organic association finish a certain specific function the procedure. Interface + procedure can solve a</p>

50、<p>　　In computer system's any software, is by the every large or small each kind of software constituent constitution, defers to the specific algorithm to realize respectively, the algorithm quality direct dec

51、ision realizes the software performance fit and unfit quality. Designs the algorithm with any method, what resources designs the algorithm to need, requires how many running time, how many storage space, how to determine

52、 an algorithm the quality, when realizes a software, is must give to solve. </p><p>　　The algorithm is the problem-solving step, we may define the algorithm Cheng Jie a determination class question the rando

53、m one special method. In the computer science, the algorithm needs to use the computer algorithmic language to describe, the algorithm represents with the computer solves a kind of question precisely, the effective metho

54、d. The algorithm construction of data = procedure, solves one to assign may calculate or the solvable question, the different person may compile the different </p><p>　　ASP.NET技術(shù)和VB語言</p><p>　　A

55、SP.NET是一個(gè)統(tǒng)一的Web開發(fā)模型，它包括您使用盡可能少的代碼生成企業(yè)級(jí)Web應(yīng)用程序所必需的各種服務(wù)。ASP.NET 作為.NET Framework的一部分提供。當(dāng)您編寫 ASP.NET應(yīng)用程序的代碼時(shí)，可以訪問.NET Framework 中的類。您可以使用與公共語言運(yùn)行庫 (CLR) 兼容的任何語言來編寫應(yīng)用程序的 代碼，這些語言包括Microsoft Visual Basic、C#、JScript .NET 和 J#。使

56、用這些語言，可以開發(fā)利用公共語言運(yùn)行庫、類型安全、繼承等方面的優(yōu)點(diǎn)的 ASP.NET 應(yīng)用程序。ASP.NET 包括：頁和控件框架、ASP.NET 編譯器、安全基礎(chǔ)結(jié)構(gòu)、狀態(tài)管理功能、應(yīng)用程序配置、運(yùn)行狀況監(jiān)視和性能功能、調(diào)試支持、XML Web services框架、可擴(kuò)展的宿主環(huán)境和應(yīng)用程序生命周期管理、可擴(kuò)展的設(shè)計(jì)器環(huán)境。</p><p>　　ASP.NET頁和控件框架是一種編程框架，它在Web服務(wù)器上運(yùn)行

57、，可以動(dòng)態(tài)地生成和呈現(xiàn)ASP.NET網(wǎng)頁?？梢詮娜魏螢g覽器或客戶端設(shè)備請求ASP.NET 網(wǎng)頁，ASP.NET 會(huì)向請求瀏覽器呈現(xiàn)標(biāo)記（例如 HTML）。通常，您可以對(duì)多個(gè) 瀏覽器使用相同的頁，因?yàn)?ASP.NET 會(huì)為發(fā)出請求的瀏覽器呈現(xiàn)適當(dāng)?shù)臉?biāo)記。 但是，您可以針對(duì)諸如 Microsoft Internet Explorer 6 的特定瀏覽器設(shè)計(jì) ASP.NET 網(wǎng)頁，并利用該瀏覽器的功能。ASP.NET 支持基于Web的設(shè)備（如移

58、動(dòng)電話、手持型計(jì)算機(jī)和個(gè)人數(shù)字助理 (PDA)的移動(dòng)控件。</p><p>　　ASP.NET 網(wǎng)頁是完全面向?qū)ο蟮摹Ｔ?ASP.NET 網(wǎng)頁中，可以使用屬性、方法和事件來處理HTML元素。ASP.NET頁框架為響應(yīng)在服務(wù)器上運(yùn)行的代碼中的客戶端事件提供統(tǒng)一的模型，從而使您不必考慮基于Web的應(yīng)用程序中固有的客戶端和服務(wù)器隔離的實(shí)現(xiàn)細(xì)節(jié)。該框架還會(huì)在頁處理生命周期中自動(dòng)維護(hù)頁及 該頁上控件的狀態(tài)。 </p&

59、gt;<p>　　使用ASP.NET頁和控件框架還可以將常用的UI功能封裝成易于使用且可重用的控件。控件只需編寫一次，即可用于許多頁并集成到ASP.NET網(wǎng)頁中。這些控件在呈現(xiàn)期間放入ASP.NET網(wǎng)頁中。</p><p>　　ASP.NET 頁和控件框架還提供各種功能，以便可以通過主題和外觀來控制網(wǎng)站的整體外觀和感覺?？梢韵榷x主題和外觀，然后在頁面級(jí)或控件級(jí)應(yīng)用這些主題和外觀。</p>

60、;<p>　　除了主題外，還可以定義母版頁，以使應(yīng)用程序中的頁具有一致的布局。一 個(gè)母版頁可以定義您希望應(yīng)用程序中的所有頁（或一組頁）所具有的布局和標(biāo)準(zhǔn) 行為。然后可以創(chuàng)建包含要顯示的頁特定內(nèi)容的各個(gè)內(nèi)容頁。當(dāng)用戶請求內(nèi)容頁 時(shí)，這些內(nèi)容頁與母版頁合并， 產(chǎn)生將母版頁的布局與內(nèi)容頁中的內(nèi)容組合在一起的輸出。</p><p>　　所有ASP.NET代碼都經(jīng)過了編譯，可提供強(qiáng)類型、性能優(yōu)化和早期綁定以

61、及其他優(yōu)點(diǎn)。代碼一經(jīng)編譯，公共語言運(yùn)行庫會(huì)進(jìn)一步將ASP.NET編譯為本機(jī) 代碼，從而提供增強(qiáng)的性能。</p><p>　　ASP.NET包括一個(gè)編譯器，該編譯器將包括頁和控件在內(nèi)的所有應(yīng)用程序組件編譯成一個(gè)程序集，之后ASP.NET宿主環(huán)境可以使用該程序集來處理用戶請求。</p><p>　　除了.NET 的安全功能外，ASP.NET還提供了高級(jí)的安全基礎(chǔ)結(jié)構(gòu)，以便對(duì)用戶進(jìn)行身份驗(yàn)證和授

62、權(quán)，并執(zhí)行其他與安全相關(guān)的功能。您可以使用由 IIS 提 供的Windows身份驗(yàn)證對(duì)用戶進(jìn)行身份驗(yàn)證，也可以通過您自己的用戶數(shù)據(jù)庫 使用ASP.NET Forms身份驗(yàn)證和ASP.NET成員資格來管理身份驗(yàn)證。此外，可 以使用Windows組或您自己的自定義角色數(shù)據(jù)庫（使用ASP.NET角色）來管理Web應(yīng)用程序的功能和信息方面的授權(quán)。您可以根據(jù)應(yīng)用程序的需要方便地移 除、添加或替換這些方案。</p><p>

63、　　ASP.NET始終使用特定的Windows標(biāo)識(shí)運(yùn)行，因此，您可以通過使用Windows功能（例如NTFS訪問控制列表(ACL)、數(shù)據(jù)庫權(quán)限等等）來保護(hù)應(yīng)用 程序的安全。</p><p>　　ASP.NET提供了內(nèi)部狀態(tài)管理功能，它使您能夠存儲(chǔ)頁請求期間的信息，例如客戶信息或購物車的內(nèi)容。您可以保存和管理應(yīng)用程序特定、會(huì)話特定、頁特定、用戶特定和開發(fā)人員定義的信息。此信息可以獨(dú)立于頁上的任何控件。</p&

64、gt;<p>　　ASP.NET提供了分布式狀態(tài)功能，使您能夠管理一臺(tái)計(jì)算機(jī)或數(shù)臺(tái)計(jì)算機(jī)上同一 應(yīng)用程序的多個(gè)實(shí)例的狀態(tài)信息。</p><p>　　通過 ASP.NET 應(yīng)用程序使用的配置系統(tǒng)，可以定義Web服務(wù)器、網(wǎng)站或單個(gè)應(yīng)用程序的配置設(shè)置。您可以在部署ASP.NET應(yīng)用程序時(shí)定義配置設(shè)置，并 且可以隨時(shí)添加或修訂配置設(shè)置，且對(duì)運(yùn)行的 Web 應(yīng)用程序和服務(wù)器具有最小 的影響。ASP.NET 配

65、置設(shè)置存儲(chǔ)在基于XML的文件中。由于這些XML文件是ASCII文本文件，因此對(duì)Web應(yīng)用程序進(jìn)行配置更改比較簡單。您可以擴(kuò)展配 置方案，使其符合自己的要求。</p><p>　　ASP.NET 包括可監(jiān)視ASP.NET應(yīng)用程序的運(yùn)行狀況和性能的功能。使用ASP.NET運(yùn)行狀況監(jiān)視可以報(bào)告關(guān)鍵事件，這些關(guān)鍵事件提供有關(guān)應(yīng)用程序的運(yùn) 行狀況和錯(cuò)誤情況的信息。 這些事件顯示診斷和監(jiān)視特征的組合，并在記錄哪些事件以及如何

66、記錄事件等方面提供了高度的靈活性。</p><p>　　ASP.NET支持兩組可供應(yīng)用程序訪問的性能計(jì)數(shù)器：ASP.NET 系統(tǒng)性能計(jì)數(shù)器組、ASP.NET應(yīng)用程序性能計(jì)數(shù)器組。</p><p>　　ASP.NET 利用運(yùn)行庫調(diào)試基礎(chǔ)結(jié)構(gòu)來提供跨語言和跨計(jì)算機(jī)調(diào)試支持。可以調(diào)試托管和非托管對(duì)象，以及公共語言運(yùn)行庫和腳本語言支持的所有語言。 </p><p>　　此外

67、，ASP.NET頁框架提供使您可以將檢測消息插入 ASP.NET 網(wǎng)頁的跟蹤 模式。</p><p>　　ASP.NET支持XML Web services。XML Web services 是包含業(yè)務(wù)功能的組 件，利用該業(yè)務(wù)功能，應(yīng)用程序可以使用HTTP和XML消息等標(biāo)準(zhǔn)跨越防火墻 交換信息。XML Web services不用依靠特定的組件技術(shù)或?qū)ο笳{(diào)用約定。因此， 用任何語言編寫、使用任何組件模型并在任何操

68、作系統(tǒng)上運(yùn)行的程序，都可以訪 問 XML Web services。</p><p>　　ASP.NET 包括一個(gè)可擴(kuò)展的宿主環(huán)境，該環(huán)境控制應(yīng)用程序的生命周期，即從用戶首次訪問此應(yīng)用程序中的資源（例如頁）到應(yīng)用程序關(guān)閉這一期間。雖然ASP.NET依賴作為應(yīng)用程序宿主的Web服務(wù)器(IIS)，ASP.NET自身也提供 但了許多宿主功能。通過ASP.NET的基礎(chǔ)結(jié)構(gòu)，您可以響應(yīng)應(yīng)用程序事件并創(chuàng)建 自定義HTTP處理

69、程序和HTTP模塊。</p><p>　　ASP.NET中提供了對(duì)創(chuàng)建Web服務(wù)器控件設(shè)計(jì)器（用于可視化設(shè)計(jì)工具， 例如Visual Studio）的增強(qiáng)支持。 使用設(shè)計(jì)器可以為控件生成設(shè)計(jì)時(shí)用戶界面，這樣開發(fā)人員可以在可視化設(shè)計(jì)工具中配置控件的屬性和內(nèi)容。</p><p>　　Microsoft Visual Basic(簡稱VB)是在Windows操作平臺(tái)下設(shè)計(jì)應(yīng)用程序的最速度、最簡捷

70、的工具之一。不論是初學(xué)者還是專業(yè)開發(fā)人員，VB都為他們提供了一整套的工具，可以輕松方便的開發(fā)應(yīng)用程序。因此，VB一直被作為大多數(shù)電腦初學(xué)者的首選入門編程語言。</p><p>　　“Visual”指的是采用可視化的開發(fā)圖形用戶界面（GUI）的方法，一般不需要編寫大量代碼去描述界面元素的外觀和位置，而只要把需要的控件拖放到屏幕上的相應(yīng)位置即可方便圖形設(shè)計(jì)圖形用戶界面；“Basic”指的是BASIC語言，因?yàn)閂B是在

71、原有的BAISC語言的基礎(chǔ)上發(fā)展起來的。</p><p>　　VB是Microsoft的一種通用程序設(shè)計(jì)語言，它包括在Microsoft Excel、Microsoft Access等眾多Windows應(yīng)用軟件中的VBA都使用VB語言，以供用戶進(jìn)行二次開發(fā)；目前制作網(wǎng)頁使用較多的VBScript腳本語言也是VB的子集。</p><p>　　利用VB的數(shù)據(jù)訪問特性用戶可以對(duì)包括 Micros

72、oft SQL Server和其他企業(yè)數(shù)據(jù)庫在內(nèi)的大部分?jǐn)?shù)據(jù)庫格式創(chuàng)建數(shù)據(jù)庫和前端應(yīng)用程序，以及可調(diào)整的服務(wù)端部件。利用ActiveX(TM)技術(shù)，VB可使用Microsoft Word字處理器、Microsoft Excel電子數(shù)據(jù)表極其他Windows應(yīng)用程序提供的功能，甚至可直接使用由VB專業(yè)版或企業(yè)版創(chuàng)建的應(yīng)用程序和對(duì)象。</p><p>　　用戶最終創(chuàng)建的程序是一個(gè)真正的.EXE文件，可以自由發(fā)布。&l

73、t;/p><p><b>　　1、集成開發(fā)環(huán)境</b></p><p>　　VB的集成環(huán)境或稱IDE，由多個(gè)部分組成，包含了標(biāo)題欄、菜單欄、工具欄、控件箱，以及窗體設(shè)計(jì)器窗口、工程管理器窗口、屬性窗口、代碼窗口和窗體布局窗體布局等。覆蓋了開發(fā)應(yīng)用程序的設(shè)計(jì)、編輯、編譯和調(diào)試等所有功能。</p><p>　　在VB中，應(yīng)用程序也稱工程。當(dāng)?shù)谝淮螁?dòng)V

74、B并打開一個(gè)新工程時(shí)，可以看到如圖所示的集成開發(fā)環(huán)境界面。</p><p>　　VB通過工程來組織應(yīng)用程序的開發(fā)，使用工程來管理構(gòu)成應(yīng)用程序的所有文件。一個(gè)工程一般由若干個(gè)窗體、標(biāo)準(zhǔn)模塊以及應(yīng)用環(huán)境組成。系統(tǒng)通過工程菜單來對(duì)工程進(jìn)行管理，如添加窗體、引用等。系統(tǒng)允許同時(shí)打開和管理多個(gè)工程。</p><p><b>　　2、語言簡介</b></p><

75、;p>　　Basic是最常被用來做入門使用的高級(jí)語言。它的全名是 Beginner’s All-purpose Sumbolic Instruction Code，簡稱為BASIC。顧名思義，Basic就是一種專為初學(xué)者設(shè)計(jì)的語言，因其易學(xué)易懂，所以身受歡迎。早期的Basic語言都是屬于解譯式的，因此可以一行一行地執(zhí)行，所以它可以立刻看到執(zhí)行的結(jié)果，對(duì)初學(xué)者來說這是很方便的設(shè)計(jì)。不過它也因此沒有結(jié)構(gòu)化的概念，在程序的維護(hù)及管理上比

76、起其他語言困難許多。不過在后期的Basic則改正了以上的缺點(diǎn)（如Quick Basic），使得它也可以用來開發(fā)較大型的程序。</p><p>　　語言是構(gòu)成VB程序的基本成分。VB規(guī)定了語句格式和功能。 語句定義符用于規(guī)定語句的功能，語句體指定語句的具體內(nèi)容或要執(zhí)行的具體操作。所有語句的集合就是VB語言，用VB語句進(jìn)行有機(jī)組合完成某個(gè)特定功能就是程序。界面+程序就能解決某個(gè)應(yīng)用問題。</p><

77、;p>　　3.編程對(duì)象響應(yīng)的程序代碼</p><p>　　VB應(yīng)用程序代碼一般在“代碼編輯器”窗口編寫。“代碼編輯器”像是一個(gè)高度專門化的字處理軟件，有很多便于編寫VB代碼的功能。</p><p>　　VB的數(shù)據(jù)庫編程方面按其難易程度可分為三類(由易到難)：</p><p>　　①使用數(shù)據(jù)庫控制項(xiàng)和綁定控制項(xiàng) ②使用數(shù)據(jù)庫對(duì)象變量進(jìn)行編程 ③直接調(diào)用ODBC2

78、.0API</p><p>　　在使用VB進(jìn)行數(shù)據(jù)庫編程時(shí),通常,會(huì)首先選擇三種基本方法之一來進(jìn)行數(shù)據(jù)庫應(yīng)用程序的方案設(shè)計(jì), 現(xiàn)在就將以上三種設(shè)計(jì)方法的適應(yīng)范圍及其優(yōu)缺點(diǎn)進(jìn)行一個(gè)比較。</p><p>　　1. 使用數(shù)據(jù)庫控制項(xiàng)和綁定控制項(xiàng) </p><p><b>　　1.1優(yōu)點(diǎn)</b></p><p>　?、偎侨N

79、方法中編碼量最小的</p><p>　?、诓槐亓私釩DBC2.0API的細(xì)節(jié)</p><p>　　③允許使用標(biāo)準(zhǔn)的和第三方廠商制訂的控制項(xiàng)</p><p><b>　?、芎喕隋e(cuò)誤處理</b></p><p>　?、葜С炙械膭?dòng)態(tài)集方法及屬性 </p><p><b>　　1.2缺點(diǎn)&l

80、t;/b></p><p>　　①不能存取快照對(duì)象(snapshop)對(duì)象或表格對(duì)象(都屬于記錄集對(duì)象) 不能存取數(shù)據(jù)庫集合,比如表定義(TableDefs)字段(Fieds),索引( Indexes)及查詢定義(QueryDefs)</p><p>　?、谥荒艽嫒〔糠諳DBC2.0管理函數(shù)</p><p>　?、鄄荒苓M(jìn)行真正的事務(wù)處理 </p>

81、<p>　?、苡邢薜腻e(cuò)誤診斷功能 </p><p><b>　　1.3應(yīng)用</b></p><p>　　①對(duì)中小規(guī)模的數(shù)據(jù)庫表(通常少于一千條記錄)只進(jìn)行簡章的瀏覽操作</p><p>　?、诨維QL查詢所對(duì)應(yīng)的結(jié)果集長度有限(通常結(jié)果集的記錄數(shù)小于一百, 這些記錄從一個(gè)或兩個(gè)長度有限的表中檢索出來)</p><

82、;p>　　③應(yīng)用程序的數(shù)據(jù)輸入/輸出項(xiàng)較少(通常只涉及一個(gè)或兩個(gè)長度有限的表、并且表中的字段數(shù)在10個(gè)左右且不具有關(guān)系完整性限制</p><p>　　2. 使用數(shù)據(jù)庫對(duì)象變量進(jìn)行編程</p><p><b>　　2.1 優(yōu)點(diǎn)</b></p><p>　?、倏梢栽诔绦蛑写嫒DBC2.0的管理函數(shù)</p><p>　

83、?、诳梢钥刂贫喾N記錄集類型：Dynaset、Snapshop及Table記錄集合對(duì)象 </p><p>　?、劭梢源嫒〈鎯?chǔ)過程和查詢動(dòng)作</p><p>　?、芸梢源嫒?shù)據(jù)庫集合對(duì)象，例如TableDefs、Fields、Indexes及QueryDefs 具有真正的事務(wù)處理能力, 包括啟動(dòng)事務(wù)(Begintrans)、提交事務(wù)(CommitTrans)及回滾事務(wù)(Rollback)<

84、;/p><p><b>　　2.2 缺點(diǎn)</b></p><p>　　①比使用數(shù)據(jù)控制項(xiàng)的方法編碼量較大 </p><p>　?、谥荒苓M(jìn)行間接的錯(cuò)誤處理和錯(cuò)誤恢復(fù) </p><p>　　③對(duì)每個(gè)數(shù)據(jù)庫操作沒有細(xì)粒度的控制</p><p>　?、軐?duì)結(jié)果集和包含結(jié)果集的內(nèi)豐資源的操作受到限制 </p

85、><p>　?、萃苯邮褂肙DBC2.0API函數(shù)的方法相比性能較低 </p><p><b>　　2.3 應(yīng)用</b></p><p>　　①應(yīng)用程序需要在執(zhí)行期間動(dòng)態(tài)地建立表、字段及索引</p><p>　　②應(yīng)用程序涉及同步更新幾張表(但在邏輯上保持一致性)的復(fù)雜事務(wù)</p><p>　?、蹜?yīng)用

86、程序使用結(jié)果集而不是Dynaset的窗體(FORMS)，例如Snapshots或Tables，這里是設(shè)計(jì)要考慮的關(guān)鍵</p><p>　?、軕?yīng)用程序的表非常大，多于1000條記錄</p><p>　?、輵?yīng)用程序具有復(fù)雜的數(shù)據(jù)輸入/輸出項(xiàng)，它涉及許多內(nèi)部相關(guān)的字段并且包括數(shù)據(jù)庫參照完整性或一致性規(guī)則</p><p>　　⑥應(yīng)用程序需要執(zhí)行一些額外的操作和對(duì)結(jié)果集的查詢

87、后處理，尤其是需要很高的數(shù)據(jù)格式化顯示</p><p>　?、邞?yīng)用程序需要利用復(fù)雜的ODBC管理功能以選擇、配置、校驗(yàn)及建立各種數(shù)據(jù)源 </p><p>　?、鄳?yīng)用程序需要在執(zhí)行期間“顯示”數(shù)據(jù)庫的基本結(jié)構(gòu) </p><p>　?、釕?yīng)用程序需要使用復(fù)雜的多碼索引方式來檢索或更新記錄</p><p>　　3. 直接調(diào)用ODBC2.0API &l

88、t;/p><p><b>　　3.1 優(yōu)點(diǎn)</b></p><p>　?、倏梢灾苯訁⑴c結(jié)果集的開發(fā)、管理及規(guī)范化</p><p>　　②對(duì)結(jié)果集游標(biāo)提供了更多的控制，并且提供了更多的游標(biāo)類型和執(zhí)行動(dòng)作 ③能夠確定ODBC驅(qū)動(dòng)程序及SQL的一致性級(jí)別</p><p>　?、芸梢愿玫乜刂芖indows的執(zhí)行調(diào)度及資源利用<

89、;/p><p>　?、萜渌矫嫱渌椒ú畈欢?因此這種方法很可能具有最好的性能 </p><p><b>　　3.2 缺點(diǎn)</b></p><p>　?、佥^其他兩種方法需要大量的代碼</p><p>　　②代碼復(fù)雜并且要求程序員具有編制API調(diào)用的經(jīng)驗(yàn)</p><p>　?、墼诰W(wǎng)絡(luò)上Visual B

90、asic運(yùn)行期間庫的錯(cuò)誤處理缺乏安全性,因此代碼運(yùn)行期間出現(xiàn)的錯(cuò)誤所造成的后果會(huì)非常嚴(yán)重</p><p><b>　　3.3 應(yīng)用</b></p><p>　?、偃绻到y(tǒng)環(huán)境為客戶機(jī)/服務(wù)器模式下的大規(guī)模多用戶環(huán)境,那么應(yīng)用程序必須都能夠準(zhǔn)確地解決可能出現(xiàn)的系統(tǒng)錯(cuò)誤和失敗</p><p>　?、趹?yīng)用程序強(qiáng)調(diào)資源使用,這里如何對(duì)內(nèi)存、 網(wǎng)絡(luò)服務(wù)器