Restful風格wcf調用3——Stream

寫在前面

上篇文章介紹了restful接口的增刪改查，本篇文章將介紹，如何通過數據流進行文件的上傳及下載操作。

系列文章

Restful風格wcf調用

Restful風格wcf調用2——增刪改查

一個例子

添加一個wcf服務，並在global.asax中注冊路由，並修改svc文件的標記，添加Factory屬性。

   //注冊路由
            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" %>

契約

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>
        /// 根據圖片的相對路徑獲取文件流
        /// </summary>
        /// <param name="imgUrl"></param>
        /// <returns></returns>
        [OperationContract]
        [WebGet(UriTemplate = "api/{imagUrl}")]
        Stream GetImageStream(string imgUrl);
        /// <summary>
        /// 上傳圖片
        /// </summary>
        /// <param name="imgStream"></param>
        /// <param name="imageName"></param>
        [OperationContract]
        [WebInvoke(UriTemplate = "api/{imageName}", Method = "POST")]
        void UploadImage(Stream imgStream, string imageName);
        /// <summary>
        /// 獲得所有圖片的相對路徑
        /// </summary>
        /// <returns></returns>
        [OperationContract]
        [WebGet(UriTemplate = "api/list", ResponseFormat = WebMessageFormat.Xml)]
        string[] GetImages();
    }
}

實現

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>
        /// 根據圖片的相對路徑獲取文件流
        /// </summary>
        /// <param name="imgUrl"></param>
        /// <returns></returns>
        public System.IO.Stream GetImageStream(string imgUrl)
        {
            var contentType = Path.GetExtension(imgUrl).Trim('.');
            WebOperationContext woc = WebOperationContext.Current;
            //根據請求的圖片類型，動態設置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>
        /// 上傳圖片
        /// </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>
        /// 獲得所有圖片的相對路徑
        /// </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，進行上傳文件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("上傳成功");
            }
            catch (Exception)
            {
                
                throw;
            }

客戶端提示

查看Images目錄，1.jpg已經上傳成功。

通過restful服務在瀏覽器中查看：在瀏覽器中發送get請求，將會調用GetImageStream方法，將stream響應給瀏覽器，瀏覽器進行渲染。

還剩最后一個接口測試，返回所有的圖片。因為wcf寄宿的也是一個web站點，所以也可以通過在瀏覽器中直接調用，將會返回所有的圖片的相對路徑的xml信息並在頁面上進行展示。

總結

本文介紹了restful接口如何處理post過來的stream，以及如何返回stream給客戶端的方式，這里也是一種上傳下載文件的一種方式。

參考資料

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