WCF面向服務(wù)應(yīng)用程序系列之五契約版本管理

1、WCF面向服務(wù)應(yīng)用程序系列之五契約版本管理一版本相容性開發(fā)環(huán)境：VisualStudio2010+NetFramework4.0。服務(wù)契約的變化對(duì)客戶端產(chǎn)生的阻礙如下：服務(wù)契約的變化對(duì)現(xiàn)存客戶端的阻礙在操作簽名上添加新的參數(shù)客戶端町M、能被阻礙新的參數(shù)在服務(wù)中被初始化為缺省值從操作簽名中刪除參數(shù)客戶端町M、能被阻礙客戶端傳遞的余外參數(shù)將被忽略，這些數(shù)據(jù)在服務(wù)端被丟失修改參數(shù)類型如果從客戶端進(jìn)入的類型無(wú)法轉(zhuǎn)換為參數(shù)的數(shù)據(jù)類型，將會(huì)拋出專門修改返回?cái)?shù)值的類型如果從服務(wù)端返回的值無(wú)法轉(zhuǎn)換為在客戶端操作簽名中所期望的數(shù)據(jù)類型，那么將會(huì)拋出添加新的操作客戶端町M、能被阻礙由于客戶端不明白新加入操作的存在

2、，因此其可不能被調(diào)用卜除操作拋出專口客戶端發(fā)送給服務(wù)端的消息會(huì)被認(rèn)為使用了未知的action頭數(shù)據(jù)契約為變化對(duì)客戶端產(chǎn)生的阻礙如下:數(shù)據(jù)契約的變化對(duì)現(xiàn)存客戶端的阻礙添加新的non-required成員客戶端町M、能被阻礙缺少的數(shù)值將會(huì)被初始化為缺省值添加新的required成員關(guān)于缺少的值，將會(huì)拋出專門刪除non-required成員服務(wù)端數(shù)據(jù)丟失無(wú)法將全部數(shù)據(jù)集返回給客戶端口小R匕拋出?？趧h除required成員當(dāng)客戶端收到來(lái)自服務(wù)端帶有缺失數(shù)據(jù)的響應(yīng)時(shí)，將會(huì)拋出專門修改已存的成員的數(shù)據(jù)類型如果類型兼容，那么可不能產(chǎn)生專門，然而可能會(huì)導(dǎo)致未知的結(jié)果下面通過DEMO來(lái)演示服務(wù)端數(shù)據(jù)契約的變化對(duì)

3、現(xiàn)存客戶端的阻礙：1、新增一個(gè)WCFServiceLibrary程序，修改解決方案名稱為Contractversion,修改項(xiàng)目名稱為ExplicitContract,刪除白動(dòng)添加的文件。2、新建Item.cs類，代碼如下：注意注釋部分。3、創(chuàng)建服務(wù)接口文件IExplicitService.cs,代碼如下：4、創(chuàng)建ExplicitService.cs類文件，代碼如下：publicclassExplicitService:IExplicitServiceprivateItem_item;publicvoidSaveItem(Itemitem)this._item=item;publicItemG

4、etItem()this._item.Message="IExplicitService.GetItem()invoked."returnthis._item;5、修改App.config中的服務(wù)名稱、端點(diǎn)契約、服務(wù)地址,代碼如下：碰代碼<?xmlversion="1.0"encoding="utf-8”?><configuration><system.web><compilationdebug="true"/></system.web><!-Whendepl

5、oyingtheservicelibraryproject,thecontentoftheconfigfilemustbeaddedtothehost'sapp.configfile.System.Configurationdoesnotsupportconfigfilesforlibraries.-><system.serviceModel><services><servicename="ExplicitContract.ExplicitService"><host><baseAddresses>&

6、lt;addbaseAddress="http:/localhost:8732/Design_Time_Addresses/ExplicitContract/ExplicitService/"/></baseAddresses></host><!-ServiceEndpoints-><!-Unlessfullyqualified,addressisrelativetobaseaddresssuppliedabove-><endpointaddress=""binding="wsHttp

7、Binding"contract="ExplicitContract.IExplicitService"><!-Upondeployment,thefollowingidentityelementshouldberemovedorreplacedtoreflecttheidentityunderwhichthedeployedserviceruns.Ifremoved,WCFwillinferanappropriateidentityautomatically.-><identity><dnsvalue="localh

8、ost"/></identity></endpoint><!-MetadataEndpoints-><!-TheMetadataExchangeendpointisusedbytheservicetodescribeitselftoclients.-><!-Thisendpointdoesnotuseasecurebindingandshouldbesecuredorremovedbeforedeployment-><endpointaddress="mex"binding="mex

9、HttpBinding"contract="IMetadataExchange"/></service></services><behaviors><serviceBehaviors><behavior><!-Toavoiddisclosingmetadatainformation,setthevaluebelowtofalseandremovethemetadataendpointabovebeforedeployment-><serviceMetadatahttpGetEnab

10、led="True”/><!-Toreceiveexceptiondetailsinfaultsfordebuggingpurposes,setthevaluebelowtotrue.Settofalsebeforedeploymenttoavoiddisclosingexceptioninformation-><serviceDebugincludeExceptionDetailInFaults="False"/></behavior></serviceBehaviors></behaviors>

11、</system.serviceModel></configuration>6、創(chuàng)建客戶端操縱臺(tái)程序Client,添加ServiceReference修改名稱空間為TestExplicitContract,并添加測(cè)試TestExplicitContract方法,代碼如下：田e代碼7、設(shè)置Client為啟動(dòng)項(xiàng)目，運(yùn)行調(diào)試ExplicitContract程序，然后，將在操縱臺(tái)看到如下輸出：TestExplicitContractBeginInputexittoclosetheclient,otherscontinue.Pleaseinputtheid:88Youhavein

12、putitem.IdContract:88Pleaseinputthename:xinhaijulanYouhaveinputitem.NameContract:xinhaijulanGetfromserveritem.IdContractis:88Getfromserveritem.NameContractis:xinhaijulanapzp.ctMiligifDrjehw,hem.csQICiplint&eFviDE.-rs-CupIhdterwicE-.c?£AppxcnfigPr&graffijcsfiftGetfromr-serveritem?Message

13、ContractisiiExplicitServ-icevGetItemOinvokEoiblic&KlicitSrwic'Mitrac.ClLiEin.lercbsintCmfieur&liorJ3wi»>fttuiEcencita&ddteEE:ed.他*迪心*湖心財(cái)*做*eE曹工十土匚費(fèi)&頭1.二aJ+uxiliinLHn«t«JLddjTIIiIInputexiI'to"closetheclient,otherscontinue1心MLSyithSbe學(xué)禎眥加L.ir-1I-ra-notBAddtWEB】I.&痢修改mem.cs前聆代碼，把注釋去掉，新增屬性：p-aarrrtervnhsijijlBnTOnn/dernorErplitkCoptractnteri,eDate,.E使用”sRequired=frue；重新-生成服務(wù)端ExplicitContract項(xiàng)目，不n'Eipi/TKhEiE五戶卜珂和IqmtmEfdcFm/EwIk成dfact'語(yǔ)nfltoMpccttd.更新客尸端ServiceReference設(shè)置Client為Contract棒序，然后，將看到如下今門：Creat啟動(dòng)項(xiàng)目，運(yùn)行調(diào)試Explicit9、修改Item.cs