利用WebService发布图片文件

服务器端：

1.新建一个Asp.net空网站RGImageServer。

2.新建一个WebService项目ImageService，项目新增文件ImageService.asmx，添加方法GetTile()。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.IO;
using System.Configuration;

namespace RGImageServer
{
    /// <summary>
    /// ImageServices 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]
    // 若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务，请取消对下行的注释。
    // [System.Web.Script.Services.ScriptService]
    public class ImageServices : System.Web.Services.WebService
    {

        [WebMethod]
        public string HelloWorld()
        {
            return "Hello World";
        }
        private byte[] Stream2Bytes(Stream theStream)
        {
            int num;
            MemoryStream stream = new MemoryStream();
            while ((num = theStream.ReadByte()) != -1)
            {
                stream.WriteByte((byte)num);
            }
            theStream.Close();
            return stream.ToArray();
        }
        [WebMethod]
        public void GetTile(string imageName)
        {
            string filename = ConfigurationManager.AppSettings["ImagePath"] + @"" + imageName;
            HttpContext context = this.Context;
            if (File.Exists(filename))
            {
                try
                {
                    FileStream theStream = File.OpenRead(filename);
                    context.Response.ContentType = "image/png";
                    byte[] buffer = Stream2Bytes(theStream);
                    context.Response.OutputStream.Write(buffer, 0, buffer.Length);
                }
                catch (Exception)
                {
                    context.Response.StatusCode = 500;
                }
            }
        }
    }
}

3.配置WebConfig文件，发布服务。

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

<!--
  有关如何配置 ASP.NET 应用程序的详细消息，请访问
  http://go.microsoft.com/fwlink/?LinkId=169433
  -->

<configuration>
  <system.web>
    <compilation debug="true" targetFramework="4.0" />
    <webServices>
      <protocols>
        <add name="HttpGet" />
        <add name="HttpPost" />
        <add name="HttpSoap" />
      </protocols>
    </webServices>
  </system.web>
  <appSettings>
    <add key="ImagePath" value="E:"/>
  </appSettings>
</configuration>

客户端：

1.调用下载图片代码如下：

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        Stream ContentStream;
        HttpWebResponse response = null;
        string ContentType;
        string ContentEncoding;
        int ContentLength = 0;
        int BytesProcessed;
        private void button1_Click(object sender, EventArgs e)
        {
            ImageServices server = new ImageServices();
            string Url = "http://localhost:6235/ImageServices.asmx/GetTile?imageName=aa.png";
            string SavedFilePath = "D:\bb.png";
            // Download to file
            string targetDirectory = Path.GetDirectoryName(SavedFilePath);
            if (targetDirectory.Length > 0)
                Directory.CreateDirectory(targetDirectory);
            ContentStream = new FileStream(SavedFilePath, FileMode.Create);
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
            request.ContentType = "text/xml";
            using (response = request.GetResponse() as HttpWebResponse)
            {
                // only if server responds 200 OK
                if (response.StatusCode == HttpStatusCode.OK)
                {
                    ContentType = response.ContentType;
                    ContentEncoding = response.ContentEncoding;

                    // Find the data size from the headers.
                    string strContentLength = response.Headers["Content-Length"];
                    if (strContentLength != null)
                    {
                        ContentLength = int.Parse(strContentLength);
                    }
                    //缓存字节数组，大小1500byte
                    byte[] readBuffer = new byte[1500];
                    using (Stream responseStream = response.GetResponseStream())
                    {
                        while (true)
                        {
                            //  Pass do.readBuffer to BeginRead.
                            int bytesRead = responseStream.Read(readBuffer, 0, readBuffer.Length);
                            if (bytesRead <= 0)
                                break;
                            ContentStream.Write(readBuffer, 0, bytesRead);
                            BytesProcessed += bytesRead;
                        }
                    }
                    ContentStream.Close();
                    ContentStream.Dispose();
                    ContentStream = null;
                }
            }


        }
    }

 

以下是一个一般处理程序ImageHandler用于图片发布，添加ImageHandler.ashx： 

using System;
using System.Web;
using System.Configuration;
using System.IO;

namespace RGImageServer
{
    /// <summary>
    /// ImageHandler 的摘要说明
    /// </summary>
    public class ImageHandler : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            //context.Response.ContentType = "text/plain";
            //context.Response.Write("Hello World");

            string imageName = "aa.png";
            string filename = ConfigurationManager.AppSettings["ImagePath"] + @"" + imageName;
            if (File.Exists(filename))
            {
                try
                {
                    FileStream theStream = File.OpenRead(filename);
                    context.Response.ContentType = "image/png";
                    byte[] buffer = StreamToBytes(theStream);
                    context.Response.OutputStream.Write(buffer, 0, buffer.Length);
                }
                catch (Exception)
                {

                }
            }
        }
        private byte[] StreamToBytes(Stream theStream)
        {
            int num;
            MemoryStream stream = new MemoryStream();
            while ((num = theStream.ReadByte()) != -1)
            {
                stream.WriteByte((byte)num);
            }
            theStream.Close();
            return stream.ToArray();
        }
        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

 通过浏览器可以直接访问：http://localhost:6235/ImageHandler.ashx