Download ASP.NET and Web Programming

UniversityCollegeofSoutheastNorway
ASP.NET
WebProgramming
Hans-PetterHalvorsen,2016.11.01
http://home.hit.no/~hansha
TableofContents
1 Introduction........................................................................................................................4
1.1 VisualStudio.................................................................................................................4
1.2 C#.................................................................................................................................5
1.3 .NETFramework...........................................................................................................5
1.4 Object-OrientedProgramming(OOP)..........................................................................5
2 VisualStudio........................................................................................................................7
2.1 Introduction.................................................................................................................7
2.2 GettingStarted.............................................................................................................7
2.2.1 IntegratedDevelopmentEnvironment(IDE)........................................................7
2.2.2 NewProject...........................................................................................................8
2.2.3 SolutionExplorer...................................................................................................9
2.2.4 Toolbox..................................................................................................................9
2.2.5 EditorsandDesigners..........................................................................................10
2.2.6 Propertieswindow..............................................................................................11
2.2.7 BuildandDebugTools.........................................................................................12
3 IntroductiontoWebProgramming...................................................................................13
3.1 Introduction...............................................................................................................13
3.2 WebBrowser..............................................................................................................14
3.3 HTML..........................................................................................................................14
3.4 CSS..............................................................................................................................15
3.5 JavaScript...................................................................................................................15
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TableofContents 3.6 ASP.NET......................................................................................................................16
3.7 AJAX/ASP.NETAJAX...................................................................................................16
3.8 Silverlight....................................................................................................................16
4 IntroductiontoASP.NET...................................................................................................18
4.1 Introduction...............................................................................................................18
4.2 ASP.NETWebPages...................................................................................................20
4.3 ASP.NETSPA...............................................................................................................20
4.4 ASP.NETMVC.............................................................................................................20
4.5 ASP.NETWebForms..................................................................................................21
5 ASP.NETWebForms.........................................................................................................22
5.1 HelloWorldExample..................................................................................................22
6 InternetInformationServices(IIS)....................................................................................26
6.1 WebServer.................................................................................................................26
7 WorkingwithDatabasesinASP.NET.................................................................................27
7.1 DatabaseSystems......................................................................................................27
7.1.1 MirosoftSQLServer............................................................................................27
7.2 SQL.............................................................................................................................27
7.3 SQLServer+ASP.NET.................................................................................................29
7.3.1 SimpleDatabaseExamplee.................................................................................29
7.4 ADO.NET.....................................................................................................................31
7.4.1 Example...............................................................................................................31
8 WebServices.....................................................................................................................35
9 Example:WeatherSystem................................................................................................36
Tutorial:ASP.NETandWebProgramming
1 Introduction
ASP.NETisaframeworkforcreatingwebsites,appsandserviceswithHTML,CSSand
JavaScript.
1.1 VisualStudio
MicrosoftVisualStudioisanintegrateddevelopmentenvironment(IDE)fromMicrosoft.It
canbeusedtodevelopconsoleandgraphicaluserinterfaceapplicationsalongwith
WindowsFormsapplications,websites,webapplications,andwebservicesinbothnative
codetogetherwithmanagedcodeforallplatformssupportedbyMicrosoftWindows,
WindowsPhone,WindowsCE,.NETFramework,.NETCompactFrameworkandMicrosoft
Silverlight.
Belowweseetheintegrateddevelopmentenvironment(IDE)inVisualStudio:
Newprojectsarecreatedfromthe“NewProject”window:
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Introduction 1.2 C#
C#ispronounced“seesharp”.C#isanobject-orientedprogramminglanguageandpartof
the.NETfamilyfromMicrosoft.C#isverysimilartoC++andJava.C#isdevelopedby
MicrosoftandworksonlyontheWindowsplatform.
1.3 .NETFramework
The.NETFramework(pronounced“dotnet”)isasoftwareframeworkthatrunsprimarilyon
MicrosoftWindows.Itincludesalargelibraryandsupportsseveralprogramminglanguages
whichallowlanguageinteroperability(eachlanguagecanusecodewritteninother
languages).The.NETlibraryisavailabletoalltheprogramminglanguagesthat.NET
supports.Programswrittenforthe.NETFrameworkexecuteinasoftwareenvironment,
knownastheCommonLanguageRuntime(CLR),anapplicationvirtualmachinethat
providesimportantservicessuchassecurity,memorymanagement,andexceptionhandling.
TheclasslibraryandtheCLRtogetherconstitutethe.NETFramework.
1.4 Object-OrientedProgramming(OOP)
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Introduction Object-orientedprogramming(OOP)isaprogramminglanguagemodelorganizedaround
"objects"ratherthan"actions"anddataratherthanlogic.Historically,aprogramhasbeen
viewedasalogicalprocedurethattakesinputdata,processesit,andproducesoutputdata.
ThefirststepinOOPistoidentifyalltheobjectsyouwanttomanipulateandhowthey
relatetoeachother,anexerciseoftenknownasdatamodeling.Onceyou'veidentifiedan
object,yougeneralizeitasaclassofobjectsanddefinethekindofdataitcontainsandany
logicsequencesthatcanmanipulateit.Eachdistinctlogicsequenceisknownasamethod.A
realinstanceofaclassiscalledan“object”oran“instanceofaclass”.Theobjectorclass
instanceiswhatyouruninthecomputer.Itsmethodsprovidecomputerinstructionsand
theclassobjectcharacteristicsproviderelevantdata.Youcommunicatewithobjects-and
theycommunicatewitheachother.
ImportantfeatureswithOOPare:
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ClassesandObjects
Inheritance
Polymorphism
Encapsulation Simulawasthefirstobject-orientedprogramminglanguage.Simulawasdevelopedinthe
1960sbyKristenNygaardfromNorway.
Java,Python,C++,VisualBasic.NETandC#arepopularOOPlanguagestoday. SinceSimula-typeobjectsarereimplementedinC++,JavaandC#theinfluenceofSimulais
oftenunderstated.ThecreatorofC++(1979),BjarneStroustrup(fromDenmark),has
acknowledgedthatSimulawasthegreatestinfluenceonhimtodevelopC++.
Tutorial:ASP.NETandWebProgramming
2 VisualStudio
2.1 Introduction
HomepageofVisualStudio:http://www.microsoft.com/visualstudio
ThereexistdifferentversionsofVisualStudio,suchasVisualStudioExpress(free),Visual
StudioProfessional,VisualStudioPremiumandVisualStudioUltimate.
2.2 GettingStarted
2.2.1
IntegratedDevelopmentEnvironment(IDE)
TheVisualStudioproductfamilysharesasingleintegrateddevelopmentenvironment(IDE)
thatiscomposedofseveralelements:theMenubar,Standardtoolbar,varioustoolwindows
dockedorauto-hiddenontheleft,bottom,andrightsides,aswellastheeditorspace.The
toolwindows,menus,andtoolbarsavailabledependonthetypeofprojectorfileyouare
workingin.
BelowweseetheVisualStudioIDE(IntegratedDevelopmentEnvironment):
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2.2.2
VisualStudio NewProject Thefirstthingyoudowhenyouwanttocreateanewapplicationistocreateanewproject.
ThiscanbedonefromtheStartPage:
OrfromtheFilemenu:
Thenthe“NewProject”windowappears:
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VisualStudio Inthiswindowyouwillselectanappropriatetemplatebasedonwhatkindofapplicationyou
wanttocreate,andanameandlocationforyourprojectandsolution.
Themostcommonapplicationsare:
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WindowsFormApplication
ConsoleApplication
WPFApplication
ASP.NETWebApplication
SilverlightApplication
2.2.3
SolutionExplorer
Solutionsandprojectscontainitemsthatrepresentthereferences,dataconnections,
folders,andfilesthatyouneedtocreateyourapplication.Asolutioncontainercancontain
multipleprojectsandaprojectcontainertypicallycontainsmultipleitems.
2.2.4
Toolbox
TheToolboxcontainsallthenecessarycontrols,etc.youneedtocreateyouruserinterface.
SeeFigurebelow.
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VisualStudio TheToolboxcontainsallthecontrols,etc.wecanuse
inouruserinterface.
Inordertousetheminouruserinterface,wejustdrag
anddropthemtothe“Form”,asshownbelow:
2.2.5
EditorsandDesigners
VisualStudiohasdifferenteditorsanddesigntools.
GraphicalUserInterfaceDesigner:
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VisualStudio CodeEditor:
2.2.6
Propertieswindow
EachcontrolwehaveonouruserinterfacehaslotsofPropertieswecanset.
ThisisdoneinthePropertieswindow:
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2.2.7
VisualStudio BuildandDebugTools
InVisualStudiowehavelotsofBuildandDebuggingTools. Buildmenu:
BelowweseetheBuildmenu: Themostusedtoolis“BuildSolution”(ShortcutKey:F6).
Debugmenu:
BelowweseetheDebugmenu: Themostusedtoolis“StartDebugging”(ShortcutKey:F5).
Tutorial:ASP.NETandWebProgramming
3 IntroductiontoWeb
Programming
3.1 Introduction
TodaymostoftheapplicationsfocusontheInternet,wheretheapplicationscanbeviewed
inastandardWebBrowser.StaticWebpagesarebasedonHTMLandCSS.Inordertocreate
moreadvancedapplications,weneedmorepowerfultools.
Ausefulwebsiteforlearningmoreaboutwebdevelopment:http://www.w3schools.com Importantframeworksandtoolsforcreatingdynamicwebpages:
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ASP.NET
AJAX/ASP.NETAJAX
JavaScript
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IntroductiontoWeb Silverlight
Theseframeworksandtoolswillbeexplainedbelow.
3.2 WebBrowser
ThepurposeofawebbrowseristoreadHTMLdocumentsandcomposethemintovisualor
audiblewebpages.ThebrowserdoesnotdisplaytheHTMLtags,butusesthetagsto
interpretthecontentofthepage.
TodaywehavethefollowingmajorWebBrowsers:
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InternetExplorer(byMicrosoft)
Firefox(byMozilla)
Chrome(byGoogle)
Safari(byApple)
Opera(byOperafromNorway)
3.3 HTML
HTML,whichstandsforHyperTextMarkupLanguage,isthepredominantmarkuplanguage
forwebpages.HTMListhebasicbuilding-blocksofwebpages.
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IntroductiontoWeb HTMLiswrittenintheformofHTMLelementsconsistingoftags,enclosedinanglebrackets
(like<html>),withinthewebpagecontent.HTMLtagsnormallycomeinpairslike<h1>and
</h1>.Thefirsttaginapairisthestarttag,thesecondtagistheendtag(theyarealso
calledopeningtagsandclosingtags).Inbetweenthesetagswebdesignerscanaddtext,
tables,images,etc.
BelowweseeasimpleaHTMLwebpage:
<!DOCTYPE html>
<html>
<body>
<h1>My First Heading</h1>
<p>My first paragraph.</p>
</body>
</html>
AusefulwebsiteforlearningmoreaboutHTML:http://www.w3schools.com/html 3.4 CSS
WebbrowserscanalsorefertoCascadingStyleSheets(CSS)todefinetheappearanceand
layoutoftextandothermaterial. TheW3C,maintainerofboththeHTMLandtheCSSstandards
AusefulwebsiteforlearningmoreaboutCSS:http://www.w3schools.com/css 3.5 JavaScript
JavaScriptisanobject-orientedscriptinglanguagebasicallyusedtocreatedynamicweb
pages.JavaScriptisprimarilyusedintheformofclient-sideJavaScript,implementedaspart
ofawebbrowserinordertoprovideenhanceduserinterfacesanddynamicwebsites.
BelowweseeasimpleaHTMLwebpagewithJavaScript:
<!DOCTYPE html>
<html>
<body>
<h1>My First JavaScript</h1>
<p>Click the button to display the date.</p>
<p id="demo"></p>
<button type="button" onclick="myFunction()">Try it</button>
<script>
function myFunction()
{
document.getElementById("demo").innerHTML = Date();
}
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IntroductiontoWeb </script>
</body>
</html>
AusefulwebsiteforlearningmoreaboutJavaScript:http://www.w3schools.com/js 3.6 ASP.NET
ASP.NETisawebapplicationframeworkdevelopedbyMicrosofttoallowprogrammersto
builddynamicwebsites,webapplicationsandwebservices. ASP.NETispartoftheVisualStudiopackage.
ItwasfirstreleasedinJanuary2002withversion1.0ofthe.NETFramework,andisthe
successortoMicrosoft'sActiveServerPages(ASP)technology.ASP.NETisbuiltonthe
CommonLanguageRuntime(CLR),allowingprogrammerstowriteASP.NETcodeusingany
supported.NETlanguage,suchasC#andVB.NET.
ASP.NETwebpagesorwebpage,knownofficiallyasWebForms],arethemainbuildingblock
forapplicationdevelopment.Webformsarecontainedinfileswithan“.aspx”extension.
3.7 AJAX/ASP.NETAJAX
AJAXisanacronymforAsynchronousJavaScriptandXML.AJAXisagroupofinterrelated
webdevelopmentmethodsusedontheclient-sidetocreateinteractivewebapplications.
WithAjax,webapplicationscansenddatato,andretrievedatafrom,aserver
asynchronously(inthebackground)withoutinterferingwiththedisplayandbehaviorofthe
existingpage.
ASP.NETAJAXisasetofextensionstoASP.NETdevelopedbyMicrosoftforimplementing
AJAXfunctionality.
3.8 Silverlight
MicrosoftSilverlightisanapplicationframeworkforwritingandrunningbrowserplug-insor
otherrichinternetapplications,withfeaturesandpurposessimilartothoseofAdobeFlash.
Therun-timeenvironmentforSilverlightisavailableasaplug-informostwebbrowsers.
SilverlightisalsooneofthetwoapplicationdevelopmentplatformsforWindowsPhone7/8.
ThelatestversionisSilverlight5.0.
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IntroductiontoWeb SilverlightisbasedonWPF,soinSilverlightapplications,userinterfacesaredeclaredin
ExtensibleApplicationMarkupLanguage(XAML)andprogrammedusingasubsetofthe.NET
Framework.
Tutorial:ASP.NETandWebProgramming
4 IntroductiontoASP.NET
4.1 Introduction
ASP.NETisawebapplicationframeworkdevelopedbyMicrosofttoallowprogrammersto
builddynamicwebsites,webapplicationsandwebservices. ASP.NETisaframeworkfrocreatingwebsites,appsandserviceswithHTML,CSSand
JavaScript.
WebSite:http://www.asp.net ASP.NETsupportsdifferentapproachesformakingwebsitesorwebpages. •
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ASP.NETWebPagesusesasinglepagemodelthatmixescodeandHTMLmarkup.
ASP.NETSPA(SinglePageApplication)
ASP.NETWebFormsusescontrolsandanevent-modelforcomponent-based
development. ASP.NETMVC(ModelViewController)valuesseparationofconcernsandenables
easiertest-drivendevelopment. Youcanmixandmatchthesetechniqueswithinoneapplicationdependingonyourneeds.
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IntroductiontoASP.NET Video:http://www.asp.net/aspnet/overview/making-websites-with-aspnet/making-websites-with-aspnet NewWebProjectDialog:
SelectProjectName,LoctionandSolutionName.
Next,seelctthetemplateyouwanttouse.
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IntroductiontoASP.NET 4.2 ASP.NETWebPages
InASP.NETWebPagesyouincludeservercodedirectlyintotheHTMLsyntax,similartoPHP
andClassicASP.
ASP.NETWebPagesusesSingePageModel(Theserver-sidecodeismixedinbetweenthe
HTML).ItusesthetheRazorsyntax(.cshtmlfiles)
AtoolcalledMicrosoftWebMatrixisoptimizedforthisdevelopmentmodel,butyoucan
alsouseVisualStudioifyouwantto.
http://www.w3schools.com/aspnet 4.3 ASP.NETSPA
SPA–SinglePageApplication
Formoreinformation:http://www.asp.net/single-page-application 4.4 ASP.NETMVC
MVC–Model-View–Controller
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IntroductiontoASP.NET Anewdevelopmentmodelwhereyousplityourdevelopmentinto3parts/components:
ModelsforData,ViewsforDisplayandControllersforInput.
4.5 ASP.NETWebForms
ASP.NETissimiliartothedesktopdevelopmentmodelusedinWPF. GUI(*.aspxfiles)and
Code(*.aspx.cs)isseparated.
InthisdocumentwewillfocusonASP.NETWebForms.
Tutorial:ASP.NETandWebProgramming
5 ASP.NETWebForms
ThemainfocusinthistutorialwillbeASP.NETWebForms.
5.1 HelloWorldExample
Whenyouarefinished,yourWebAppshouldlooksomethinglikethis:
WhenyouenteryourNameintheTextBoxandclicktheOKButton,theprogramshould
respondwithagreetings.
SeelctCreateNewProject:
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ASP.NETWebForms Youhavelotsofchoiceshere–butwejustwanttocreateaverysimpleWebFormApp.
CreateNewWebForm:
WinForm1.aspxPage:UsedtocreatetheGUI/HMI
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ASP.NETWebForms HelloworldExample–GUI:
WebForm1.aspx.cs:
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ASP.NETWebForms RunningtheApplication(F5):
Congratulations,youhavecreatedyourfirstASP.NETWebFormsapplication.
Tutorial:ASP.NETandWebProgramming
6 InternetInformation
Services(IIS)
6.1 WebServer
Thetermwebservercanrefertoeitherthehardware(thecomputer)orthesoftware(the
computerapplication)thathelpstodeliverwebcontentthatcanbeaccessedthroughthe
Internet.
Themostcommonuseofwebserversistohostwebsites,butthereareotherusessuchas
gaming,datastorageorrunningenterpriseapplications.
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IIS-InternetInformationServices, MicrosoftWindows
ApacheWebServer, OpenSource, Cross-platform:UNIX,Linux,OSX,Windows,...
Nginx (pronounced"enginex") -Hasbecomeverypopularlatly
GWS(GoogleWebServer)
etc.
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7 WorkingwithDatabasesin
ASP.NET
Today,mostofthewebsitesandwebpagesusesadatabasetostoredatathatisvisibleon
thewebpage,e.g.Facebook,Instagram,Twitter,etc.
7.1 DatabaseSystems
Therearelotsofdifferentdatabasesystems,orDBMS–DatabaseManagementSystems,
suchas:
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MicrosoftSQLServer
o Enterprise,Developerversions,etc.
o Expressversionisfreeofcharge
Oracle
MySQL(Oracle,previouslySunMicrosystems)-MySQLcanbeusedfreeofcharge
(opensourcelicense),WebsitesthatuseMySQL:YouTube,Wikipedia,Facebook
MariaDB(“TheNewMySQL”)
MicrosoftAccess
IBMDB2
Sybase
…lotsofothersystems
7.1.1
MirosoftSQLServer
MicrosoftisthevendorofSQLServer.WehavedifferenteditionsofSQLServer,whereSQL
ServerExpressisfreetodownloadanduse.WewillfocusonSQLServerinthistutorial.
7.2 SQL
SQL(StructuredQueryLanguage)isadatabasecomputerlanguagedesignedformanaging
datainrelationaldatabasemanagementsystems(RDBMS).
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WorkingwithDatabasesinASP.NET SQL,isastandardizedcomputerlanguagethatwasoriginallydevelopedbyIBMforquerying,
alteringanddefiningrelationaldatabases,usingdeclarativestatements.
SQLispronounced/ˌɛskjuːˈɛl/ (letterbyletter) or/ˈsiːkwəl/ (asaword).
WhatcanSQLdo?
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SQLcanexecutequeriesagainstadatabase
SQLcanretrievedatafromadatabase
SQLcaninsertrecordsinadatabase
SQLcanupdaterecordsinadatabase
SQLcandeleterecordsfromadatabase
SQLcancreatenewdatabases
SQLcancreatenewtablesinadatabase
SQLcancreatestoredproceduresinadatabase
SQLcancreateviewsinadatabase
SQLcansetpermissionsontables,procedures,andviews
EvenifSQLisastandard,manyofthedatabasesystemsthatexisttodayimplementtheir
ownversionoftheSQLlanguage.InthisdocumentwewillusetheMicrosoftSQLServeras
anexample. HerearesomeexamplesofSQLqueries:
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WorkingwithDatabasesinASP.NET InthisTutorialwewillfocusonMicrosoftSQLServer.SQLServerusesT-SQL(Transact-SQL).
T-SQLisMicrosoft'sproprietaryextensiontoSQL.T-SQLisverysimilartostandardSQL,but
inadditionitsupportssomeextrafunctionality,built-infunctions,etc.
InordertousedatabasesinourapplicationsweneedtoknowStructuredQuerylanguage
(SQL).FormoreinformationaboutSQL,seethefollowingTutorial:StructuredQuery
Language(SQL)
TheTutorialsareavailablefrom:http://home.hit.no/~hansha
7.3 SQLServer+ASP.NET
SQLServer+ASP.NET=PowerfulWebApplications
7.3.1
SimpleDatabaseExamplee
CreateaDatabasecalledLIBRARYandaBOOKtableinSQLServer.EntersomeTestdatainto
theBOOKtable.
Filla“GridView”withdatafromtheDatabaseTable(BOOK),asshownbelow
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WorkingwithDatabasesinASP.NET Usethe“Wizard”inordertocreateallthe“magic”youneedinyourapplication:
Whenfinishingthe“Wizard”,your.aspxpageshouldlooksomethinglikethis Asyousee-NoCodeneededtobewritteninthisexampleJ
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WorkingwithDatabasesinASP.NET ThisisOKforquickdemos–butforprofessionalapplications,youneedtousesome
hardcoreADO.NETorsimiliarframeworks.
7.4 ADO.NET
ADO.NET(ActiveXDataObjectfor.NET)isasetofcomputersoftwarecomponentsthat
programmerscanusetoaccessdataanddataservices.Itisapartofthebaseclasslibrary
thatisincludedwiththeMicrosoft.NETFramework.Itiscommonlyusedbyprogrammersto
accessandmodifydatastoredinrelationaldatabasesystems,thoughitcanalsoaccessdata
innon-relationalsources.
7.4.1
Example
Thistime:CreateeverythingfromscratchusingC#codeandADO.NET. Filla
“DropDownList”withBookNamesfromtheDatabase PrinttheAuthorNamebasedon
theselectedBookNameonthescreen,seebelow.
Your.aspxpageshouldlooksomethinglikethis: Tutorial:ASP.NETandWebProgramming
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WorkingwithDatabasesinASP.NET Your.aspx.cspageshouldlooksomethinglikethis:
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WorkingwithDatabasesinASP.NET ThePage_load()methodisexecutedwhentheWebPageisloaded.Inthissimpleexample
weputallthecodeintotheEventHandlerfortheDropDownList.Thecodecouldbe
improvedbycreatingaseparateClasswhereyouputthiscodeintoaMethod.
TheFillBookListmethodisasfollows:
ThecodecouldbeimprovedbycreatingaseparateClasswhereyoucreatethisMethod.
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WorkingwithDatabasesinASP.NET AllkindogconfigurationshouldbestoredintheWeb.configfile,includingDatabase
ConnectionStrings,etc.
Tutorial:ASP.NETandWebProgramming
8 WebServices
InordertosharedatabetweendevicesoverInternet,WebServicesisthesolution.
InASP.NETthereareseveralalternativesforcreatingsuchWebServices.
SeetheTutorial“WebServiceswithExamples”formoredetails.
VisualStudioandASP.NEThaspowerfulfeaturesforcreatingWebServices:
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ASMXWebService(TraditionalWebWerviceusingSOAP)
ASP.NETWebAPI(ThemodernWebServiceusingREST,Web2.0)
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9 Example:WeatherSystem
BelowweseeanexampleofaWebSitecreatedinASP.NET.TheWebSitepresentweather
datafromtheWeatherstationlocatedatTelemarkUniversityCollege.
Formoreinformation,pleasevisit:
http://home.hit.no/~hansha/weather.htm 36
Hans-PetterHalvorsen,M.Sc.
E-mail:[email protected]
Blog:http://home.hit.no/~hansha/
UniversityCollegeofSoutheastNorway
www.usn.no