Restful风格wcf调用3——Stream

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

Restful风格wcf调用

Restful风格wcf调用2——增删改查

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
    {
        /// <summary>
        /// 根据图片的相对路径获取文件流
        /// </summary>
        /// <param name="imgUrl"></param>
        /// <returns></returns>
        [OperationContract]
        [WebGet(UriTemplate = "api/{imagUrl}")]
        Stream GetImageStream(string imgUrl);
        /// <summary>
        /// 上传图片
        /// </summary>
        /// <param name="imgStream"></param>
        /// <param name="imageName"></param>
        [OperationContract]
        [WebInvoke(UriTemplate = "api/{imageName}", Method = "POST")]
        void UploadImage(Stream imgStream, string imageName);
        /// <summary>
        /// 获得所有图片的相对路径
        /// </summary>
        /// <returns></returns>
        [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
    {
        /// <summary>
        /// 根据图片的相对路径获取文件流
        /// </summary>
        /// <param name="imgUrl"></param>
        /// <returns></returns>
        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);
        }
        /// <summary>
        /// 上传图片
        /// </summary>
        /// <param name="imgStream"></param>
        /// <param name="imageName"></param>
        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);

        }
        /// <summary>
        /// 获得所有图片的相对路径
        /// </summary>
        /// <returns></returns>
        public string[] GetImages()
        {
            List<string> lstImages = new List<string>();
            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