試驗(yàn)設(shè)備管理信息系統(tǒng)之結(jié)束語(yǔ)和程序語(yǔ)言說(shuō)明重點(diǎn)復(fù)習(xí)過(guò)程

1、題 目實(shí)驗(yàn)設(shè)備管理信息系統(tǒng)結(jié)束語(yǔ)時(shí)間如白駒過(guò)隙，轉(zhuǎn)瞬即逝，三個(gè)月的畢業(yè)設(shè)計(jì)結(jié)束了，在這段時(shí)間里，我 們沒(méi)有虛度光陰，相反我們獲益匪淺。這是一次難得的練兵機(jī)會(huì)，像這樣系統(tǒng)的, 完整的做一個(gè)系統(tǒng)，機(jī)會(huì)不多，有指導(dǎo)老師從旁指導(dǎo)，更是難得。在做設(shè)計(jì)的過(guò) 程中，我碰到了困難，但沒(méi)有怨天尤人，更不會(huì)放棄，我選擇迎難而上。只有不 斷的給自己充電，才能戰(zhàn)勝困難，不斷成長(zhǎng)。這段時(shí)間學(xué)到的東西，記憶相當(dāng)深 刻，無(wú)論是技能上還是思想上，我都學(xué)到了很多東西，這是我的一大財(cái)富。只要 相信自己，就能成功。期待在將來(lái)的路途上，創(chuàng)造更加輝煌的成績(jī)。參考文獻(xiàn)1 劉刀桂，孟繁晶.Visual C+ 實(shí)踐與提高數(shù)據(jù)庫(kù)篇M.中國(guó)鐵道

2、出版社,2003.10-308.2 RobHawthorne.SQL Server 2000 數(shù)據(jù)庫(kù)開(kāi)發(fā)從零開(kāi)始M.人民郵電出版社,2004.2.254-355.3 梁方明.SQL Server2000數(shù)據(jù)庫(kù)編程M.北京希望電子社,2005.10.23-318.4 啟明.Visual C+ +SQL Server數(shù)據(jù)庫(kù)應(yīng)用系統(tǒng)開(kāi)發(fā)與實(shí)例M.人民郵電出 版社，2005.5.105-305. 史濟(jì)明.軟件工程M.高等教育出版社，2004.12.30-235.David M.Dikel.軟件體系結(jié)構(gòu)M.高等教育出版社，2004.5.致謝在這個(gè)特別的日子里，我首先感謝我們的母校，她為我們提供良好的學(xué)習(xí)

3、環(huán) 境，更為我們做出了拼搏進(jìn)取的榜樣， 我身為學(xué)院的學(xué)生而驕傲，在以后的人生 旅途上。我要學(xué)習(xí)母校求實(shí)進(jìn)取。接著，我要感謝我的指導(dǎo)老師，在這段畢業(yè)設(shè)計(jì)的日子里，由于老師的支持 和用心幫助，才能使得我將此系統(tǒng)完成。最后，我也要感謝軟件學(xué)院為我們提供良好的上機(jī)條件及學(xué)習(xí)的動(dòng)力。相信我的畢業(yè)設(shè)計(jì)的成功，就是給以學(xué)校的回報(bào)，因此我將會(huì)不懈努力把系統(tǒng)做好， 以表示對(duì)學(xué)校，學(xué)院，老師的感謝！程序設(shè)計(jì)語(yǔ)言語(yǔ)言是通信系統(tǒng)。程序設(shè)計(jì)語(yǔ)言由所有允許人機(jī)通信的符號(hào)、字符以及使用 規(guī)則組成。一些程序設(shè)計(jì)語(yǔ)言的產(chǎn)生是為了服務(wù)于特殊的目的（例如控制機(jī)器人），而其它一些程序設(shè)計(jì)語(yǔ)言則是比較靈活的通用工具，可適用于許多類(lèi)型的

4、 應(yīng)用。然而， 每一個(gè)程序設(shè)計(jì)語(yǔ)言必須接收確定類(lèi)型的書(shū)寫(xiě)指令以使一個(gè)計(jì)算 機(jī)系統(tǒng)能夠完成大量的熟悉的操作。換言之，每一個(gè)語(yǔ)言必須具有屬于以下為人 們所熟悉范疇的指令：1輸入/輸出指令。用于I/O設(shè)備與中央處理器之間的通信，這些指令提供了將 要完成的輸入或輸出操作類(lèi)型的細(xì)節(jié)以及操作期間將用到的存儲(chǔ)器地址。2. 計(jì)算指令。用于實(shí)現(xiàn)加、減、乘、除的指令，顯然，所有程序設(shè)計(jì)語(yǔ)言均有 此類(lèi)指令。3. 邏輯/比較指令。這些指令用于轉(zhuǎn)移程序控制，以及編寫(xiě)程序中所用到的選擇和循環(huán)結(jié)構(gòu)。在處理過(guò)程中，兩個(gè)數(shù)據(jù)項(xiàng)的比較可能是一個(gè)邏輯指令的結(jié)果。 正如你了解的那樣，程序控制能根據(jù)一個(gè)選擇測(cè)試 （如果R>0,那

5、么A,否則B） 的結(jié)果來(lái)決定其不同的路徑，而一個(gè)循環(huán)可以根據(jù)一個(gè)出口條件測(cè)試的結(jié)果（測(cè)試Q=-999?）而繼續(xù)進(jìn)行或終止。 語(yǔ)言中除了設(shè)定測(cè)試或比較以實(shí)現(xiàn)轉(zhuǎn)移程序控制的指令外，還有一些不依賴(lài)比較結(jié)果的無(wú)條件轉(zhuǎn)移指令。4. 存儲(chǔ)/檢索和傳送指令。這些指令用于處理期間的存儲(chǔ)、 檢索和傳送數(shù)據(jù)。數(shù) 據(jù)可以從一個(gè)存儲(chǔ)地址復(fù)制到另一存儲(chǔ)地址以及進(jìn)行必要的檢索。 但是，即使所有的程序設(shè)計(jì)語(yǔ)言都具有一個(gè)執(zhí)行上述這些操作的指令集， 但在機(jī) 器語(yǔ)言、匯編語(yǔ)言以及高級(jí)語(yǔ)言中所使用的符號(hào)、 字符以及語(yǔ)法方面仍有明顯的 區(qū)別。機(jī)器語(yǔ)言計(jì)算機(jī)的機(jī)器語(yǔ)言由二進(jìn)制數(shù)字串組成，并且是唯一能被CPU直接“理解” 的語(yǔ)言。任何機(jī)

6、器語(yǔ)言指令至少由兩部分組成。第一部分是命令或操作， 它告訴計(jì)算機(jī)將完成什么功能， 每一臺(tái)計(jì)算機(jī)都有一個(gè)操作碼來(lái)完成其功能。 指 令的第二部分是操作數(shù)， 它告訴計(jì)算機(jī)在哪里找到或存儲(chǔ)數(shù)據(jù)以及將要操縱的其 它指令，它們是計(jì)算機(jī)將要操縱的對(duì)象， 一條指令的操作數(shù)的數(shù)目因計(jì)算機(jī)不同 而異。在單操作數(shù)機(jī)器中，指令“ ADD0184”的二進(jìn)制值將導(dǎo)致地址 0184中的 值加到算術(shù)邏輯部件中某一寄存器的值中。在雙操作數(shù)機(jī)器中，“ ADD 0184 8672”的二進(jìn)制表示將導(dǎo)致地址 8672中的值加到地址 0184的值中。單操作數(shù)格 式在最小的微計(jì)算機(jī)中十分常見(jiàn)，而雙操作數(shù)結(jié)構(gòu)則多用于大多數(shù)其它機(jī)器。 按照今

7、天的標(biāo)準(zhǔn)， 早期的計(jì)算機(jī)實(shí)在令人難以容忍， 程序員不得不將大量指令直 接翻譯成機(jī)器能理解的機(jī)器語(yǔ)言的形式。例如，為早期的IBM機(jī)器書(shū)寫(xiě)指令“ ADD 0184”的程序員將按以下形式書(shū)寫(xiě)： 00010000000000000000000000001011100。0 除了必須記住機(jī)器指令集中大量命令的數(shù)字代碼外， 程序員還被迫跟蹤數(shù)據(jù)和指 令的存儲(chǔ)器地址分配。最早的編碼常常花費(fèi)幾個(gè)月時(shí)間， 因此非常昂貴且常常 出錯(cuò)。用于發(fā)現(xiàn)程序錯(cuò)誤的檢查指令， 與最初編程時(shí)一樣冗長(zhǎng)， 而且如果一個(gè)程 序后來(lái)必須進(jìn)行修改，則要耗費(fèi)幾周時(shí)間。匯編語(yǔ)言為了減輕程序員的負(fù)擔(dān)， 50年代初期開(kāi)發(fā)了助記符操作碼和符號(hào)地址。為

8、 了完善程序準(zhǔn)備過(guò)程， 首先要做的工作之一是用字母符號(hào) （即助記符 ）去替代數(shù)字 化的機(jī)器語(yǔ)言操作碼。 現(xiàn)在，每一個(gè)計(jì)算機(jī)都有一套助記符代碼， 當(dāng)然實(shí)際的符 號(hào)因機(jī)器類(lèi)型、 型號(hào)而異。 計(jì)算機(jī)仍使用機(jī)器語(yǔ)言處理數(shù)據(jù)， 但匯編語(yǔ)言軟件首 先把特定操作碼符號(hào)翻譯成對(duì)應(yīng)的機(jī)器語(yǔ)言。這一改進(jìn)為更進(jìn)一步的發(fā)展奠定了基礎(chǔ)。 如果計(jì)算機(jī)能較容易地將符號(hào)翻譯成基 本操作，那么它為什么不能也完成其它一些事務(wù)性的編碼功能， 諸如將存儲(chǔ)器地 址賦值成數(shù)據(jù)呢 ?符號(hào)化尋址就是這樣一個(gè)實(shí)踐， 它將地址表達(dá)為程序員方便使 用的符號(hào)而不是按照它的絕對(duì)數(shù)字地址來(lái)表示。 在符號(hào)化尋址的初期階段，程序員將一個(gè)符號(hào)名和一個(gè)真實(shí)地址

9、賦給一個(gè)數(shù)據(jù) 項(xiàng)，例如，一個(gè)月中某百貨商店顧客所購(gòu)商品的總值由程序員賦值給地址0 0 6 3并賦符號(hào)名稱(chēng)TOTAL （總值）,同一月中返回的未用商品的總值賦值給地址 2 0 4 7，取名CREDIT （賒欠）。那么，對(duì)于程序的剩余部分來(lái)說(shuō)，當(dāng)要處 理這類(lèi)數(shù)據(jù)項(xiàng)時(shí)， 程序員將使用其符號(hào)名而不是地址來(lái)進(jìn)行操作， 這樣，可以寫(xiě) 指令“CREDIT， TOTAL”，從購(gòu)買(mǎi)總值中減去返回商品的總值， 于是 匯編語(yǔ)言軟件可將該符號(hào)化指令翻譯成機(jī)器語(yǔ)言的位串：011111 011111111111 000000111111 助記符操作碼 2047 0063（S） （CREDIT） （TOTAL）此后又有了如

10、下的進(jìn)展： 程序員將分配和跟蹤指令地址的任務(wù)交由計(jì)算機(jī)完 成，程序員只要告訴機(jī)器第一個(gè)程序指令的存儲(chǔ)地址號(hào)碼， 則匯編語(yǔ)言軟件就能 自動(dòng)地從該點(diǎn)開(kāi)始依程序存放所有其它指令。 因此，如果另一指令需要加到程序 中，那么沒(méi)有必要修改插入該指令處以后的所有指令地址 （而這一修改在由機(jī)器 語(yǔ)言書(shū)寫(xiě)的程序中是必須要做的 ）。相反，下一次程序執(zhí)行時(shí)處理器將自動(dòng)調(diào)整 存儲(chǔ)地址。程序員不再像以前那樣將真實(shí)地址賦給符號(hào)化數(shù)據(jù)項(xiàng)， 現(xiàn)在他們只需說(shuō)明他們的 程序所需的第一個(gè)地址即可， 而一個(gè)匯編語(yǔ)言程序?qū)倪@里開(kāi)始執(zhí)行， 為指令和 數(shù)據(jù)分配地址空間。這一匯編語(yǔ)言程序 （或匯編程序 ），還使計(jì)算機(jī)能將程序員的匯編語(yǔ)言指

11、令翻 譯成它自己的機(jī)器代碼。在匯編語(yǔ)言中由程序員書(shū)寫(xiě)的指令程序被稱(chēng)作源程序， 當(dāng)該源程序由匯編程序轉(zhuǎn)換為機(jī)器碼后，則被稱(chēng)為目標(biāo)程序。 匯編語(yǔ)言較之機(jī)器語(yǔ)言具有許多優(yōu)點(diǎn)，它能節(jié)省時(shí)間，減少細(xì)節(jié)，較少出錯(cuò)，而 且產(chǎn)生的錯(cuò)誤也易于發(fā)現(xiàn)。 匯編語(yǔ)言書(shū)寫(xiě)的程序較之機(jī)器語(yǔ)言程序更易修改， 但 也存在一些局限， 匯編語(yǔ)言的編碼 （編程）仍然十分耗時(shí)。 匯編語(yǔ)言的一個(gè)最大的 缺陷在于它是面向機(jī)器的， 即它們是為特定的處理器而設(shè)計(jì)的， 程序在不同機(jī)器 上要重新編碼才能執(zhí)行。高級(jí)語(yǔ)言 早期的匯編程序中，一條源程序指令只產(chǎn)生一條機(jī)器指令。為了加快編碼 速度，開(kāi)發(fā)出了一種匯編程序， 它能將每一源程序指令翻譯成一數(shù)量可

12、變的機(jī)器 語(yǔ)言代碼。換句話(huà)說(shuō)，一條宏指令可以產(chǎn)生若干行機(jī)器語(yǔ)言代碼，例如，程序員 可以寫(xiě)“ READ FILE （讀文件），然后翻譯軟件會(huì)自動(dòng)地提供一系列詳盡的預(yù)先 準(zhǔn)備好的機(jī)器語(yǔ)言指令， 它們會(huì)將從輸入設(shè)備讀入的數(shù)據(jù)文件的一個(gè)記錄拷貝到 主存儲(chǔ)器中， 這樣程序員就減輕了任務(wù)， 而不必為要執(zhí)行的每一條機(jī)器操作書(shū)寫(xiě) 指令。助記符技術(shù)和宏指令的研制與開(kāi)發(fā)又反過(guò)來(lái)導(dǎo)致了高級(jí)語(yǔ)言的研制與開(kāi) 發(fā)，它們通常面向某類(lèi)特定的處理問(wèn)題。 例如，很多高級(jí)語(yǔ)言中用于處理具有科 學(xué)化數(shù)學(xué)特征的問(wèn)題，而其它一些高級(jí)語(yǔ)言則強(qiáng)調(diào)文件處理的應(yīng)用。 與匯編語(yǔ)言不同，高級(jí)語(yǔ)言程序幾乎可以不加修改地用于不同的計(jì)算機(jī)。這樣， 當(dāng)換用

13、新設(shè)備時(shí)，重編程的費(fèi)用可極大地減少。高級(jí)語(yǔ)言的其它優(yōu)點(diǎn)在于：它們比匯編語(yǔ)言更易于學(xué)習(xí)。它們只需較少時(shí)間來(lái)書(shū)寫(xiě)程序。 它們提供較好的文本。 易于維護(hù)。一個(gè)熟練的程序員， 書(shū)寫(xiě)某種高級(jí)語(yǔ)言程序時(shí)將不受某一種機(jī)器類(lèi)型的限制PROGRAMMING LANGUAGESA language is a system of communication. A programming language consists of all the symbols, characters, and usage rules that permit people to communicate with computers.

14、Some programming languages are created to serve a special purpose(e.g.,controlling a robot), while others are more flexible general-purpose tools that are suitable for many types of applications. However, every programming language must accept certain types of written instructions that will enable a

15、 computer system to perform a number of familiar operations. That is, every language must have instructions that fall into the following familiar categories:1. Input/output instructions. Required to permit communication betweenI/O devices and the central processor, these instructions provide details

16、 on the type of input or output operation to be performed and the storage locations to be used during the operation.2. Calculation instructions. Instructions to permit addition, subtraction, multiplication, and division during processing are, of course, common in all programming languages.3. Logic/c

17、omparison instruction. These instructions are used to transfer program control, and are needed in the selection and loop structures that are followed to prepare programs. During process ing, two data items maybe compared as a result of the executio n of logic in struct ion.As you know,program con tr

18、ol can follow differe nt paths depe nding on the outcome of a selectio n test(IF R>0 THEN A, ELSE B). And a loop can be contin ued or termin ated depe nding on the outcome of an exit con diti on test(doesQ=-99.9?). In additi on to the in struct ions in Ian guages that set up tests or comparisons

19、to effect the transfer of program control, there are also uncon diti onal tran sfer in structi ons available that are not based on the outcome of comparis ons.4. Storage/retrieval and moveme nt in struct ions. These in structio ns are used to store, retrieve, and move data duri ng process ing. Data

20、may be copied from one storage locati on to ano ther and retrieved as n eeded.But eve n though all program ming Ian guages have an in structi on set that permits these familiar operatio ns to be performed, there's a marked differenee to be found in the symbols, characters, and syntax of machine

21、Ian guages,assemblyIan guages, and high-level la nguages.Mach ine Lan guagesA computer's mach ine Ian guage con sists of stri ngs of binary nu mbersand is the only one the CPU directly "un dersta nds". An in structio n prepared in any machine Ianguage will have at least two parts. The

22、first part is the commanobr operation, and it tells the computer what function to perform. Every computer has an operati on code or "op code" for each of its fun cti ons. Thesec ond part of the in structi on is the opera nd, andit tells the computer where to find or store the data or other

23、 instructions that are to be man ipulated. The nu mber of opera nds in an in struct ion varies among computers. In a sin gle-opera nd mach ine, the binary equivale nt of"ADD0184" could cause the value in address 0184 to be added to the value stored in a register in the arithmetic-logic un

24、it. In a two-opera ndmachi ne, the binary represe ntation for "ADD 0184 8672" could cause thevalue in address 8672 to be added to the nu mber in locati on 0184. Thesin gle-opera nd format is popular in the smallest microcomputers; the two-opera nd structure is likely to be available in mos

25、t other mach in es.By today's sta ndards, early computers were in tolera nt. Programmers hadto tran slate in structi ons directly into the machi ne-la nguage form that computers un derstood. For example, the programmer writi ng the in struct ion to "ADD 0184" for an early IBM machi ne

26、would have writte n: 000100000000000000000000000010111000In additi on to rememberi ng the doze ns of code nu mbers for thecomma nds in the machi ne's in structi on set, a programmer was also forcedto keep track of the storage locati ons of data and in structi ons. Thein itial cod ing ofte n took

27、 mon ths, was therefore quite expe nsive, and ofte n resulted in error. Check ing in structio ns to locate errors was about as tedious as writ ing them in itially. And if a program had to be modified at a later date, the work invo Ived could take weeks to fin ish.Assembly Lan guagesTo ease the progr

28、ammer's burde n, mnemonic operati on codes andsymbolic addresses were developed in the early 1950s. One of the first steps in impro ving the program preparati on process was to substitute letter symbols mn emo nics- for the nu meric machi ne Ian guage operati oncodes. Each computer now has a mne

29、monic code, although, of course, the actual symbols vary amongmakesand models. Machine Ianguage is still used by the computer as it processes data, but assemblyIan guagesoftware first translates the specified operation code symbol into its machine-language equivalent.And this improvement sets the st

30、age for further advances. If the computer could translate convenient symbols into basic operations, why couldn't it also perform other clerical coding functions such as assigning storage addresses to data? Symbolic addressing is the practice of expressing an address not in terms of its absolute

31、numerical location, but rather in terms of symbols convenient to the programmer.In the early stages of symbolic addressing, the programmer assigned a symbolic nameand an actual address to a data item. For example, the total value of merchandise purchased during a month by a department store customer

32、 might be assigned to address 0063 by the programmer and given the symbolic name TOTAL. The value of merchandise returned unused during the month might be assigned to address 2047 and given the symbolic nameCREDIT. Then, for the remainder of the program, the programmer would refer to the symbolicnam

33、es rather than to the addresses when such itemswere to be processed. Thus, an instruction might be written "S CREDIT,TOTAL" to subtract the value of returned goods from the total amount purchased.The assembly language software might then translate the symbolic instruction into this machine

34、-language string of bits: 011111 011111111111 000000111111 Mnemonic op code 2047 0063(s) (CREDIT) (TOTAL)Another improvement followed. The programmer turned the task of assigning and keeping track of instruction addresses over to the computerDBg1(6)db0. The programmer merely told the machine the sto

35、rage address number of the first program instruction, and the assembly language software then automatically stored all others in sequence from that point. So if ano ther in struct ion was added to the program later, it was not n ecessary to modify the addresses of all in structio ns that followed th

36、e point of in serti on (as would have to be done in the case of programs writte n in mach ine Ian guage). I nstead, the processor automatically adjusted storage locati ons the n ext time the program ran.Programmers no Ion ger assig n actual address nu mbers to symbolic data items as they did earlier

37、. Now they merely specify where they want the first locati on in the program to be, and an assembly Ian guage program takes it from there, allocati ng locati ons for in structio ns and data.This assembly program, or assembler, also en ables the computer to convert the programmer's assembly Ian g

38、uage in structi ons into its own mach ine code. A program of in structi ons writte n by a programmer in an assembly Ian guage is called a source program. After this source program has bee n con verted into machi ne code by an assembler, it's referred to as an object program.Assembly Ian guages h

39、ave adva ntages over machi ne Ian guages. Theysave time and reduce detail. Fewer errors are made, and those that are made are easier to find. And assembly programs are easier for people to modify than machine-language programs. But there are limitations. Coding in assembly Ian guage is still time co

40、nsuming. And a big drawback of assembly Ian guages is that they are machi ne orie nted. That is, they are designed for the specific makeand model of processor being used. Programs might have to be recoded for a differe nt mach ine.High-LevelLan guagesThe earlier assembly programs produced only one machine instruction for each source program in struct ion.To speed up codi ng, assembly programswere developed that could produce a variable amount of mach in e-la nguage code for each source program instruction. In other words, a single macro ins