使用WCF上传数据

通过传递Stream对象来传递大数据文件，但是有一些限制:

1、只有 BasicHttpBinding、NetTcpBinding 和 NetNamedPipeBinding 支持传送流数据。

2、 流数据类型必须是可序列化的 Stream 或 MemoryStream。

3、 传递时消息体(Message Body)中不能包含其他数据。

4、TransferMode的限制和MaxReceivedMessageSize的限制等。

下面具体实现：新建一个FileService，接口文件的代码如下：

using System.IO;
using System.ServiceModel;

namespace FileService
{
    
    [ServiceContract]
    public interface IFileService
    {
        [OperationContract]
        void UpLoadFile(FileUploadMessage fileUploadMessage);
    }

    [MessageContract]
    public class FileUploadMessage
    {
        [MessageHeader]
        public string FileName
        {
            get;
            set;
        }

        [MessageBodyMember]
        public Stream FileData
        {
            get;
            set;
        }
    }
}

定义FileUploadMessage类的目的是因为第三个限制，要不然文件名及其他信息就没办法传递给WCF了，根据第二个限制，文件数据是用System.IO.Stream来传递的。下面是接口的具体实现。

using System;
using System.IO;

namespace FileService
{
    public class FileService : IFileService
    {
        //保存文件的目录路径
        private const string SaveDirectory = @"F:\V2.4ShareFolder\PRO";

        public void UpLoadFile(FileUploadMessage fileUploadMessage)
        {
            string fileName = fileUploadMessage.FileName;

            Stream sourceStream = fileUploadMessage.FileData;

            FileStream targetStream = null;

            if (!sourceStream.CanRead)
            {
                throw new Exception("数据流不可读!");
            }

            string filePath = Path.Combine(SaveDirectory, fileName);

            using (targetStream = new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.None))
            {
                //read from the input stream in 4K chunks
                //and save to output stream
                const int bufferLen = 4096;

                var buffer = new byte[bufferLen];

                try
                {
                    int count;

                    while ((count = sourceStream.Read(buffer, 0, bufferLen)) > 0)
                    {
                        targetStream.Write(buffer, 0, count);
                    }
                }
                finally
                {
                    sourceStream.Close();
                }
            }
        }
    }
}

实现的功能很简单，把文件保存到特定的目录中即可。下面是进行config的配置。

<?xml version="1.0" encoding="utf-8" ?>
<configuration>

  <appSettings>
    <add key="aspnet:UseTaskFriendlySynchronizationContext" value="true" />
  </appSettings>
  <system.web>
    <compilation debug="true" />
  </system.web>
  <!-- When deploying the service library project, the content of the config file must be added to the host's 
  app.config file. System.Configuration does not support config files for libraries. -->
  <system.serviceModel>
    <bindings>
      <basicHttpBinding>
        <binding name="FileServiceBinding" maxReceivedMessageSize="10485760" transferMode="Streamed"></binding>
      </basicHttpBinding>
    </bindings>
    <services>
      <service name="FileService.FileService" behaviorConfiguration="FileServiceBehavior">
        <host>
          <baseAddresses>
            <add baseAddress="http://localhost:9090/FileService"/>
          </baseAddresses>
        </host>
        <endpoint address="" binding="basicHttpBinding" contract="FileService.IFileService" bindingConfiguration="FileServiceBinding"/>
        <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
      </service>
    </services>
    <behaviors>
      <serviceBehaviors>
        <behavior name="FileServiceBehavior">
          <!-- To avoid disclosing metadata information, 
          set the values below to false before deployment -->
          <serviceMetadata httpGetEnabled="True" httpsGetEnabled="True"/>
          <!-- To receive exception details in faults for debugging purposes, 
          set the value below to true.  Set to false before deployment 
          to avoid disclosing exception information -->
          <serviceDebug includeExceptionDetailInFaults="False" />
        </behavior>
      </serviceBehaviors>
    </behaviors>
  </system.serviceModel>

</configuration>

新建客户端，进行服务的测试。

namespace TestClient
{
    class Program
    {
        static void Main(string[] args)
        {
            FileServiceClient fileServiceClient = new FileServiceClient();

            string filepath = @"F:\V2.4ShareFolder\EPHMDY1031975917464876001-7131898.zip";

            using (Stream stream = new FileStream(filepath, FileMode.Open))
            {
                fileServiceClient.UpLoadFile("222.zip", stream);
            }

            Console.ReadKey();
        }
    }
}