System.ServiceModel.CommunicationException：The underlying connection was closed: The connection was closed unexpectedly

在开发WCF的过程中，发现了当请求数据量超过了一定大小的时候，就报异常：

System.ServiceModel.CommunicationException：The underlying connection was closed: The connection was closed unexpectedly

先看服务器：

 

<? xml version="1.0" encoding="utf-8" ?>
< configuration >
   < configSections >
     < section  name ="cachingConfiguration"  type ="Microsoft.Practices.EnterpriseLibrary.Caching.Configuration.CacheManagerSettings, Microsoft.Practices.EnterpriseLibrary.Caching, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"  requirePermission ="true"   />
   </ configSections >
   < cachingConfiguration  defaultCacheManager ="Session" >
     < cacheManagers >
       < add  name ="Session"  type ="Microsoft.Practices.EnterpriseLibrary.Caching.CacheManager, Microsoft.Practices.EnterpriseLibrary.Caching, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"  expirationPollFrequencyInSeconds ="60"  maximumElementsInCacheBeforeScavenging ="10000"  numberToRemoveWhenScavenging ="10"  backingStoreName ="NullBackingStore"   />
     </ cacheManagers >
     < backingStores >
       < add  type ="Microsoft.Practices.EnterpriseLibrary.Caching.BackingStoreImplementations.NullBackingStore, Microsoft.Practices.EnterpriseLibrary.Caching, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"  name ="NullBackingStore"   />
     </ backingStores >
   </ cachingConfiguration >
   < system.web >
     < compilation  debug ="true"  targetFramework ="4.0" >
       < assemblies >
         < add  assembly ="System.Data.Entity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"   />
       </ assemblies >
     </ compilation >
   </ system.web >
   < system.serviceModel >
     <!-- 该值指示此服务是否在 ASP.NET HTTP 应用程序管道的上下文中运行 -->
     < serviceHostingEnvironment  aspNetCompatibilityEnabled ="true"  multipleSiteBindingsEnabled ="true"   />
     < services >
       < service  name ="WmsService.Service"  behaviorConfiguration ="XRServiceBehavior" >
         < endpoint  bindingConfiguration ="BasicHttpBinding"  binding ="basicHttpBinding"  contract ="WmsService.IService"   />
       </ service >
     </ services >
     < behaviors >
       < serviceBehaviors >
         < behavior  name ="XRServiceBehavior" >
           < serviceMetadata  httpGetEnabled ="true"   />
           < serviceDebug  httpHelpPageEnabled ="false"  includeExceptionDetailInFaults ="true"   />
         </ behavior >
       </ serviceBehaviors >
     </ behaviors >
     < bindings >
       < basicHttpBinding >
         < binding  name ="BasicHttpBinding"  allowCookies ="true"  maxReceivedMessageSize ="2147483647"  maxBufferPoolSize ="2147483647"  maxBufferSize ="2147483647" >
           < readerQuotas  maxDepth ="2147483647"  maxStringContentLength ="2147483647"  maxArrayLength ="2147483647"  maxBytesPerRead ="2147483647"  maxNameTableCharCount ="2147483647"   />
           < security  mode ="None" >
             < transport  clientCredentialType ="None"  proxyCredentialType ="None"  realm =""   />
             < message  clientCredentialType ="UserName"  algorithmSuite ="Default"   />
           </ security >
         </ binding >
       </ basicHttpBinding >
     </ bindings >
   </ system.serviceModel >
   < system.webServer >
     < modules  runAllManagedModulesForAllRequests ="true"   />
   </ system.webServer >
  </ configuration >

 

 

再看客户端：

 

<? xml version="1.0" encoding="utf-8" ?>
< configuration >
   < system.serviceModel >
     < bindings >
       < basicHttpBinding >
         < binding  name ="BasicHttpBinding_IService"  allowCookies ="true"  maxReceivedMessageSize ="2147483647"  maxBufferPoolSize ="2147483647"  maxBufferSize ="2147483647" >
           < readerQuotas  maxDepth ="2147483647"  maxStringContentLength ="2147483647"  maxArrayLength ="2147483647"  maxBytesPerRead ="2147483647"  maxNameTableCharCount ="2147483647"   />
           < security  mode ="None" >
             < transport  clientCredentialType ="None"  proxyCredentialType ="None"  realm =""   />
             < message  clientCredentialType ="UserName"  algorithmSuite ="Default"   />
           </ security >
         </ binding >
       </ basicHttpBinding >
     </ bindings >
     < client >
       < endpoint  address ="http://localhost:3609/Service.svc"  binding ="basicHttpBinding"  bindingConfiguration ="BasicHttpBinding_IService"  contract ="WmsService.IService"  name ="BasicHttpBinding_IService"   />
     </ client >
     </ system.serviceModel >   
</ configuration >

 

 

 

通过寻找，终于找到原因：原来是behavior在作怪：在行为节点下面有一个类dataContractSerializer，此类有一个属性MaxItemsInObjectGraph，用来控制序列化对象中允许的最大项数。默认值为 65536 字节 (64KB)，一旦数据超出了该值，则抛出通信异常。解决方法：

在服务器的的行为配置下加上<dataContractSerializer maxItemsInObjectGraph="2147483647"/>

在客户端加上节点：

 

  < behaviors >
       < endpointBehaviors >
         < behavior  name ="superBehavior" >
           < dataContractSerializer
             maxItemsInObjectGraph ="2147483647"   />
         </ behavior >
       </ endpointBehaviors >
  </ behaviors >

 

然后在endpoint节点上设置属性：behaviorConfiguration="superBehavior"。

测试通过。