Question

所以我有一个wcf rest服务，它可以从一个控制台应用程序运行，如果我导航到：http://localhost:8000/Service/picture/300/400我的图像显示注意300/400设置图像的宽度和高度在html的正文中页。

代码如下所示：

namespace WcfServiceLibrary1
{
    [ServiceContract]
    public interface IReceiveData
    {
        [OperationContract]
        [WebInvoke(Method = "GET", BodyStyle = WebMessageBodyStyle.Wrapped, ResponseFormat = WebMessageFormat.Xml, UriTemplate = "picture/{width}/{height}")]
        Stream GetImage(string width, string height);
    }
    public class RawDataService : IReceiveData
    {
        public Stream GetImage(string width, string height)
        {
                int w, h;

                if (!Int32.TryParse(width, out w))
                {
                    w = 640;
                }
                // Handle error
                if (!Int32.TryParse(height, out h))
                {
                    h = 400;
                }
            Bitmap bitmap = new Bitmap(w, h); 
            for (int i = 0; i < bitmap.Width; i++)
            {
                for (int j = 0; j < bitmap.Height; j++)
                {
                    bitmap.SetPixel(i, j, (Math.Abs(i - j) < 2) ? Color.Blue : Color.Yellow);
                }
            }
            MemoryStream ms = new MemoryStream();
            bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
            ms.Position = 0;
            WebOperationContext.Current.OutgoingResponse.ContentType = "image/jpeg";
            return ms;
        }
    }
}

我现在要做的是使用客户端应用程序“我的Windows窗体应用程序”并将该图像添加到图片框中。因为我希望wcf休息服务中图像的宽度和高度由图片框的宽度和高度设置，所以我知道如何实现这一点。我试过这个但是在两行上有错误，我甚至不确定它是否会起作用我的wcf休息服务的代码用“/”分隔宽度和高度，如果你在网址中注意到的话。

    string uri = "http://localhost:8080/Service/picture";
    private void button1_Click(object sender, EventArgs e)
    {

        StringBuilder sb = new StringBuilder();
        sb.AppendLine("<picture>");
        sb.AppendLine("<width>" + pictureBox1.Image.Width + "</width>");
        // the url looks like this http://localhost:8080/Service/picture/300/400 when accessing the image so I am trying to set this here
        sb.AppendLine("<height>" + pictureBox1.Image.Height + "</height>");
        sb.AppendLine("</picture>");
        string picture = sb.ToString();
        byte[] getimage = Encoding.UTF8.GetBytes(picture); // not sure this is right
        HttpWebRequest req = WebRequest.Create(uri); //cant convert webrequest to httpwebrequest
        req.Method = "GET";
        req.ContentType = "image/jpg";
        req.ContentLength = getimage.Length; 
        MemoryStream reqStrm = req.GetRequestStream(); //cant convert IO stream to IO Memory stream
        reqStrm.Write(getimage, 0, getimage.Length); 
        reqStrm.Close();
        HttpWebResponse resp = req.GetResponse(); // cant convert web respone to httpwebresponse
        MessageBox.Show(resp.StatusDescription);
        pictureBox1.Image = Image.FromStream(reqStrm);
        reqStrm.Close();
        resp.Close();
    }

所以只是想知道是否有人可以帮我解决这个徒劳的尝试，从我的休息服务到按钮点击的图片框添加可变图像大小。

这是主机应用程序：

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            string baseAddress = "http://" + Environment.MachineName + ":8000/Service";
            ServiceHost host = new ServiceHost(typeof(RawDataService), new Uri(baseAddress));
            host.AddServiceEndpoint(typeof(IReceiveData), new WebHttpBinding(), "").Behaviors.Add(new WebHttpBehavior());
            host.Open();
            Console.WriteLine("Host opened");
            Console.ReadLine();

Answer 1

基于WinForms的方法来获取具有可变宽度和高度的图像将如下所示：

public Image GetImage(int width, int height)
{
    string uri = string.Format("http://localhost:8000/Service/picture/{0}/{1}", width, height);
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);

    using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
    {
        using (Stream stream = response.GetResponseStream())
        {
            return new Bitmap(stream);
        }
    }
}

您可以将图像放到PictureBox中，如下所示：

private void Form1_Load(object sender, EventArgs e)
{
    pictureBox.Image = GetImage(400, 500); // or any other size here
}

在WPF中你会做这样的事情：

public ImageSource GetImage(int width, int height)
{
    string uri = string.Format("http://localhost:8000/Service/picture/{0}/{1}", width, height);
    return BitmapFrame.Create(new Uri(uri));
}

Answer 2

在你的请求URL中写下关于宽度和高度参数被'/'分隔的注释，一个更RESTful的方法是将它们作为参数传递给你，例如URL看起来像：

http://localhost:8000/Service/picture?width=480&height=640

并且您的WebInvoke看起来像：

[WebInvoke(Method = "GET", BodyStyle = WebMessageBodyStyle.Wrapped, ResponseFormat = WebMessageFormat.Xml, UriTemplate = "picture?width={width}&height={height}")]

GetImage方法无需更改，参数的填充方式与原始UriTemplate相同。

WCF / REST将图像放入图片框？

2 个答案: