ASP网站制作之VBScript - The Easy Stuff - Page 2
使用cdonts,可以发送、查看邮件,实现webmail的功能。结合wsh,可以实现对nt主机的管理,如nt用户管理、iis虚拟主机设置、exchange邮箱设置等等,就像管理本地机一样方便。vbscriptVBScript-TheEasyStuff-Page2
ChrisAssenza
February5,2001
Variables
Ithinkeveryoneknowswhatavariableis,buttobesafe,avariableisalittlechunkofmemoryinwhichavalueofvaryingtype(likecharactersandnumbers)canbestoredandmanipulated.Thatisnotthemostpreciseortechnicaldefinitionthatcouldbeused,butIsuspecteveryonegetsthepicture.Variablesarewhatyouusetostorethedifferentvaluesfloatingaroundinyourprogram.AsIhintedatratherblatantlyabove,variablescantakeonmanydifferentforms.Theycanbestrings(astringisoneormorecharacters―likeasentenceforexample),integer,floatingpointnumber,adate,andallsortsofotherusefulthings.
Oneadvantagetoascriptinglanguageisthatitisnotstronglytyped.Or,inotherwords,touseavariableitdoesnotneedtobedeclaredwithatypedefined.Whereasinastrongly-typedlanguagelikeC++,youneedtodeclarenotonlythevariablebutwhattypeofvariableitis.
InVBScriptthereisreallyonlyonetype,Variant.Therefore,allVBScriptvariablesareoftypeVariant(whichmeanstheycanbasicallybeanything)andmaybeanyofthefollowingsub-types:
SUBTYPEDESCRIPTION
EmptyVariantisuninitialized.Valueis0fornumericvariablesorazero-lengthstring("")forstringvariables.
NullVariantintentionallycontainsnovaliddata.
BooleanContainseitherTrueorFalse.
ByteContainsintegerintherange0to255.
IntegerContainsintegerintherange-32,768to32,767.
Currency-922,337,203,685,477.5808to922,337,203,685,477.5807.
LongContainsintegerintherange-2,147,483,648to2,147,483,647.
SingleContainsasingle-precision,floating-pointnumberintherange-3.402823E38to-1.401298E-45fornegativevalues;1.401298E-45to3.402823E38forpositivevalues.
DoubleContainsadouble-precision,floating-pointnumberintherange-1.79769313486232E308to-4.94065645841247E-324fornegativevalues;4.94065645841247E-324to1.79769313486232E308forpositivevalues.
Date(Time)ContainsanumberthatrepresentsadatebetweenJanuary1,100toDecember31,9999.
StringContainsavariable-lengthstringthatcanbeuptoapproximately2billioncharactersinlength.
ObjectContainsanobject.
ErrorContainsanerrornumber.
Source:MicrosoftScriptingTechnologies
TheneatthingabouttheVariantthingisthatyoudonotreallyneedtoworryabouttypeatall.Itwillfigureoutwhatsub-typethevariableis,basedonhowyouuseit.Whatisimportanttorecognizeisthatifyouutilizeavariableasonesub-type(sayasaninteger)andthentrytostoreastringinitlater,thatwillreturnanerrorbecauseofamismatch.
Touseavariableincode,itfirsthastobedeclared―ormemoryspacehastobesetasideforit.VBScriptusesthe"Dim"statementtodeclarevariables(thereareothersbutwedonotneedtoworryaboutthoserightnow).HereisanexampleofusingtheDimstatement.
<%
Thislittlesingleapostropheisacomment,
itallowsyoutoputexplanationinyour
codeandnothavetheinterpreterrunit!
Usethisasnotestoyourselfforwhatcode
doesornotesforfuturedevelopersworking
onyourpage!
UsingtheDimStatement
DimmyVariable
DimanotherVariable,X,Y,count
%>
Theabovecodeisverysimplistic.ThefirstDimstatementsetsupavariablecalledmyVariable.ThesecondlinedeclaresanotherVariable,XandYallatbasicallythesametime.Itistheretosimplydemonstratethatyoucandeclaremorethenonevariableperline,aslongasyouseparateeachvariablewithacomma.
Nowbeforeyougetallexcitedandstartdeclaringvariablesuntilyourheartiscontent,youshouldknowthatthereareafewrestrictionsfornamingvariables.Theymustbeginwithanalphabeticcharacter(i.e.theycannotstartwithanumber),theycannotcontainanembeddedperiod(ie.nomy.Variabletypenamingisacceptable),theycannotexceed255characters,andtheymustbeuniquelynamed(i.e.cannothavetwodifferentvariablesnamedjiminthesamefunctionorsub).
</p>问题是他们究竟是喜欢他们是使用软件时,速度快还是速度慢好.(当然在3秒以内).无论是他们输入资料时,查找资料时,分析资料时. Request:从字面上讲就是“请求”,因此这个是处理客户端提交的东东的,例如Resuest.Form,Request.QueryString,或者干脆Request("变量名") 我想问如何掌握学习节奏(先学什么再学什么)最好详细点? 我可以结合自己的经验大致给你说一说,希望对你有所帮助,少走些弯路。 运用经典的例子。并且自己可以用他来实现一些简单的系统。如果可以对他进行进一步的修改,找出你觉得可以提高性能的地方,加上自己的设计,那就更上一个层次了,也就会真正地感到有所收获。 完全不知道到底自己学的是什么。最后,除了教程里面说的几个例子,还是什么都不会。 运用经典的例子。并且自己可以用他来实现一些简单的系统。如果可以对他进行进一步的修改,找出你觉得可以提高性能的地方,加上自己的设计,那就更上一个层次了,也就会真正地感到有所收获。 交流是必要的,不管是生活还是学习我们都要试着去交流,通过交流我们可以学到很多我们自己本身所没有的知识,可以分享别人的经验甚至经历。
页:
[1]