Question

我目前正在以字节数组的形式发送图像数据。但是，我希望以ASCII字符串形式发送它。如何在c＃中使用HTTP POST从客户端向服务器发送ASCII字符串？

    HttpWebRequest webRequest = null; 
    webRequest = (HttpWebRequest)HttpWebRequest.Create("http://192.168.1.2/"); 
    webRequest.ContentType = "application/x-www-form-urlencoded";                                            
    webRequest.Method = "POST";    

//Assume here, I got the ascii string from image using ImageToBase64() function.

byte[] buffer = encoding.GetBytes(myString)); //assume myString is an ASCII string

    // Set content length of our data 
    webRequest.ContentLength = buffer.Length; 

    webStream = webRequest.GetRequestStream(); 
    webStream.Write(buffer, 0, buffer.Length); //This is the only way I know how to send data -using byte array "buffer". But i wan to send data over as ASCII string "myString". How?
    webStream.Close(); 

    //I used this function to turn an image into ASCII string to be sent
    public string ImageToBase64(Image image, 
      System.Drawing.Imaging.ImageFormat format)
    {
      using (MemoryStream ms = new MemoryStream())
      {
        // Convert Image to byte[]
        image.Save(ms, format);
        byte[] imageBytes = ms.ToArray();

        // Convert byte[] to Base64 String
        string base64String = Convert.ToBase64String(imageBytes);
        return base64String;
      }
    }

Answer 1

我建议放弃HttpWebRequest支持WebClient。此外，如果您使用content-type application/x-www-form-urlencoded发送，则服务器将期望发布的数据与key1=value1&key2=value2的格式匹配。

// sending image to server as base 64 string
string imageBase64String = "YTM0NZomIzI2OTsmIzM0NTueYQ...";
using (WebClient client = new WebClient())
{
    var values = new NameValueCollection();
    values.Add("image", imageBase64String);
    client.UploadValues("http://192.168.1.2/", values);
}

同样的事情，但使用WebHttpRequest

string imageBase64String = "YTM0NZomIzI2OTsmIzM0NTueYQ...";
HttpWebRequest webRequest = (HttpWebRequest)HttpWebRequest.Create("http://192.168.1.2/");
webRequest.ContentType = "application/x-www-form-urlencoded";
webRequest.Method = "POST";
string formPostString = "image=" + HttpUtility.UrlEncode(imageBase64String);
byte[] buffer = ASCIIEncoding.ASCII.GetBytes(formPostString);
webRequest.ContentLength = buffer.Length;
using (Stream webStream = webRequest.GetRequestStream())
{
    webStream.Write(buffer, 0, buffer.Length);
}

然后，您可以使用HttpRequest对象在服务器端处理发送的图像。

string imageBase64String = HttpContext.Current.Request.Form["image"];

使用HTTP Post发送ASCII字符串

1 个答案: