写在前面

上篇文章介绍了restful接口的增删改查，本篇文章将介绍，如何通过数据流进行文件的上传及下载操作。

系列文章

一个例子

添加一个wcf服务，并在global.asax中注册路由，并修改svc文件的标记，添加Factory属性。

//注册路由            System.Web.Routing.RouteTable.Routes.Add(new System.ServiceModel.Activation.ServiceRoute(                "imageService", new System.ServiceModel.Activation.WebServiceHostFactory(), typeof(ImageService)));

<%@ ServiceHost Language="C#" Debug="true" Service="Wolfy.WCFRestfuleDemo.ImageService" CodeBehind="ImageService.svc.cs"  Factory="System.ServiceModel.Activation.WebServiceHostFactory" %>

契约

namespace Wolfy.WCFRestfuleDemo{    // NOTE: You can use the "Rename" command on the "Refactor" menu to change the interface name "IImageService" in both code and config file together.    [ServiceContract]    public interface IImageService    {        /// 
        /// 根据图片的相对路径获取文件流        /// 
        ///         /// 
             [OperationContract]        [WebGet(UriTemplate = "api/{imagUrl}")]        Stream GetImageStream(string imgUrl);        /// 
        /// 上传图片        /// 
        ///         ///         [OperationContract]        [WebInvoke(UriTemplate = "api/{imageName}", Method = "POST")]        void UploadImage(Stream imgStream, string imageName);        /// 
        /// 获得所有图片的相对路径        /// 
        /// 
             [OperationContract]        [WebGet(UriTemplate = "api/list", ResponseFormat = WebMessageFormat.Xml)]        string[] GetImages();    }}

实现

using System;using System.Collections.Generic;using System.Drawing;using System.IO;using System.Linq;using System.Runtime.Serialization;using System.ServiceModel;using System.ServiceModel.Web;using System.Text;namespace Wolfy.WCFRestfuleDemo{    // NOTE: You can use the "Rename" command on the "Refactor" menu to change the class name "ImageService" in code, svc and config file together.    // NOTE: In order to launch WCF Test Client for testing this service, please select ImageService.svc or ImageService.svc.cs at the Solution Explorer and start debugging.    public class ImageService : IImageService    {        /// 
        /// 根据图片的相对路径获取文件流        /// 
        ///         /// 
             public System.IO.Stream GetImageStream(string imgUrl)        {            var contentType = Path.GetExtension(imgUrl).Trim('.');            WebOperationContext woc = WebOperationContext.Current;            //根据请求的图片类型，动态设置contenttype            woc.OutgoingResponse.ContentType = "image/" + contentType;            string savePath = System.Web.HttpContext.Current.Server.MapPath("/Images");            string filePath = Path.Combine(savePath, imgUrl);            return File.OpenRead(filePath);        }        /// 
        /// 上传图片        /// 
        ///         ///         public void UploadImage(System.IO.Stream imgStream, string imageName)        {            var dir = System.Web.HttpContext.Current.Server.MapPath("~/Images");            var file = Path.Combine(dir, imageName);            var bitmap = Bitmap.FromStream(imgStream);            bitmap.Save(file);        }        /// 
        /// 获得所有图片的相对路径        /// 
        /// 
             public string[] GetImages()        {            List
     
       lstImages = new List
      
       ();            var dir = System.Web.HttpContext.Current.Server.MapPath("~/Images");            string[] paths = Directory.GetFiles(dir);            for (int i = 0; i < paths.Length; i++)            {                lstImages.Add(paths[i].Replace(dir, ""));            }            return lstImages.ToArray();        }    }}
      
     

首先，进行上传文件1.jpg

try            {                var httpClient = new HttpClient();                var strPostUrl = "http://localhost:21074/imageService/api/{0}";                string fileName = Path.GetFileName("1.jpg");                FileStream fs = new FileStream("1.jpg", FileMode.Open, FileAccess.Read, FileShare.ReadWrite);                HttpResponseMessage response = httpClient.Post(string.Format(strPostUrl, fileName), HttpContent.Create(fs));                fs.Dispose();                Console.WriteLine("上传成功");            }            catch (Exception)            {                                throw;            }

客户端提示

查看Images目录，1.jpg已经上传成功。

通过restful服务在浏览器中查看：在浏览器中发送get请求，将会调用GetImageStream方法，将stream响应给浏览器，浏览器进行渲染。

还剩最后一个接口测试，返回所有的图片。因为wcf寄宿的也是一个web站点，所以也可以通过在浏览器中直接调用，将会返回所有的图片的相对路径的xml信息并在页面上进行展示。

总结

本文介绍了restful接口如何处理post过来的stream，以及如何返回stream给客户端的方式，这里也是一种上传下载文件的一种方式。

参考资料

http://blog.csdn.net/fangxing80/article/details/6261431