我在Windows Phone上制作了一个项目，用户可以在其中拍照，将其保存在手机上，然后再上传到我的服务器上。所以有两个项目，WP8.1和ASP.NET WEB API。
目前我不知道如何将照片上传到我的服务器（来自手机），我甚至不知道如何在API中捕获它。最好的方法是什么？
这是我在屏幕（手机）上显示的方法，用户拍摄的照片。
private async void LoadCapturedphoto(string filename)
{
//load saved image
StorageFolder pictureLibrary = KnownFolders.SavedPictures;
StorageFile savedPicture = await pictureLibrary.GetFileAsync(filename);
ImageProperties imgProp = await savedPicture.Properties.GetImagePropertiesAsync();
var savedPictureStream = await savedPicture.OpenAsync(FileAccessMode.Read);
//set image properties and show the taken photo
bitmap = new WriteableBitmap((int)imgProp.Width, (int)imgProp.Height);
await bitmap.SetSourceAsync(savedPictureStream);
takenImage.Source = bitmap;
takenImage.Visibility = Visibility.Visible;
}
我认为我应该将WriteableBitmap转换为Byte []，通过API将这些Byte []发送到服务器，并在服务器上将Byte []转换为JPG / PNG /等。
private byte[] ConvertBitmapToByteArray(WriteableBitmap bitmap)
{
WriteableBitmap bmp = bitmap;
using (Stream stream = bmp.PixelBuffer.AsStream())
{
MemoryStream memoryStream = new MemoryStream();
stream.CopyTo(memoryStream);
return memoryStream.ToArray();
}
}
有什么想法吗？你觉得这样做是不错的主意？ WriteableBitmap - ＆gt; Byte []和服务器上的下一个Byte [] - ＆gt; JPG / PNG等甚至可能吗？
如果可以做得更容易，请写一些样本。
它是我调用api方法的方法
public string apiCommand(string api, string json)
{
using (var httpClient = new HttpClient())
{
HttpContent content = new StringContent(json, Encoding.UTF8);
content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
HttpResponseMessage response = httpClient.PostAsync(Variables.apiURL + api, content).Result;
response.EnsureSuccessStatusCode();
Task<string> responseBody = response.Content.ReadAsStringAsync();
//var msg = new MessageDialog(responseBody.Result.ToString());
if (response.StatusCode.ToString() != "OK")
{
return "ERROR: " + response.StatusCode.ToString();
}
else
{
return "SUCCES: " + responseBody.Result.ToString();
}
}
}
答案 0 :(得分：2)
您需要对服务器使用multipart / form-data请求。您可以使用有效负载字段将json发送到Web api（另一种方法是分别发送每个字段，但是您需要反思才能这样做。）
这可能会对你有帮助：
public string UploadUserPictureApiCommand(string api, string json, byte[] picture)
{
using (var httpClient = new HttpClient())
{
MultipartFormDataContent form = new MultipartFormDataContent();
form.Add(new StringContent(json), "payload");
form.Add(new ByteArrayContent(picture, 0, picture.Count()), "user_picture", "user_picture.jpg");
HttpResponseMessage response = await httpClient.PostAsync(api, form);
response.EnsureSuccessStatusCode();
Task<string> responseBody = response.Content.ReadAsStringAsync();
if (response.StatusCode.ToString() != "OK")
{
return "ERROR: " + response.StatusCode.ToString();
}
else
{
return "SUCCES: " + responseBody.Result.ToString();
}
}
}
答案 1 :(得分：1)
我以此方式处理项目中的图像和文字文件，希望对您有所帮助。
1）服务器端，我有一个通用的api方法来处理Json请求。
[HttpPost]
public HttpResponseMessage ProcessRequest([FromBody] string sJsonRequest)
{
ResponseMsg rspMsg = null;
RequestMsg oRequestMsg = null;
string sDeteializeMsg = "";
try
{
string sUnescapeJsonData = System.Uri.UnescapeDataString(sJsonRequest);
sJsonRequest = sUnescapeJsonData;
oRequestMsg = (RequestMsg)JsonHelper.Deserialize(typeof(RequestMsg), sJsonRequest);
}
catch (Exception ex)
{
...
}
if (oRequestMsg == null)
{
return AppHelper.GetUTF8PlainTextHttpResponse(@"Invalid request message.");
}
rspMsg = new ResponseMsg(oRequestMsg);
string sJsonRet = "";
try
{
if(oRequestMsg.RequestType==SavingFile)
{
byte[] bytes = System.Convert.FromBase64String(oRequestMsg.Base64Data);
System.IO.File.WriteAllBytes(sFileName, bytes);
....
}
//update rspMsg ....
}
catch (Exception ex)
{
...
}
finally
{
sJsonRet = JsonHelper.Serialize(rspMsg);
}
return AppHelper.GetUTF8PlainTextHttpResponse(sJsonRet);
}
客户端， 1）通过.net代码调用，我使用system.Net.webclient，
system.Net.webclient cli=new system.Net.webclient();
cli.Credentials = Credentials;
cli.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
//http://blogs.msdn.com/b/jmstall/archive/2012/04/16/how-webapi-does-parameter-binding.aspx
sJsonRequest = "=" + EscapeDataStringBig(sJsonRequest);
response = cli.UploadString(sRemoteUrl, "POST", sJsonRequest);
ResponseMsg rsp = (ResponseMsg)JsonHelper.Deserialize(typeof(ResponseMsg), response);
return rsp;
2）通过JavaScript调用它，通常我会在网站控制器中创建一个方法，并将json请求转发到上述定义的方法。如果您的JavaScript代码和api代码共享相同的json对象，则非常简单。
2.1）网站控制器代码，
[HttpPost]
public ActionResult AjaxRequest(int nPostType = -1, string sJsonObject = "")
{
try
{
WebModelAjaxRequestTypes nReqType = (WebModelAjaxRequestTypes)nPostType;
bool bIsBase64Data = IsBase64Request(nReqType);
string sJsonRet = "";
if (!bIsBase64Data)
{
....
}
else
{
//base64 content requests
string sBase64Data = sJsonObject;
//put the string into a json request and send it to api call. and get the return => sJsonRet
}
return Content(sJsonRet); }
catch (Exception ex)
{
....
}
}
2.2）JavaScript ajax调用示例代码：
var type = "POST";
var sContentType = "";
var sData = ""
if (bIsBase64) {
//sJsonParas is base64 string. don't use encodeURI to encode it.!!!
sContentType = 'application/json; charset=utf-8';
sData = '{ "nPostType" :' + nPostType.toString() + ',"sJsonObject" : "' + sJsonParas + '" }';
}
else {
sContentType = "application/x-www-form-urlencoded; charset=UTF-8";
sData = "nPostType=" + nPostType.toString() + "&sJsonObject=" + encodeURIComponent(sJsonParas);
}
jQuery.ajax({
url: sUrl,
type: type,
data: sData,
contentType: sContentType,
success: function (result) {
....
},
error: function (jqXHR, textStatus, errorThrown) {
....
},
complete: function (jqXHR, textStatus) {
....
} //end complete
});