Question

我正在使用遍布各处的几个示例中的任何一个来使用.net Web API进行文件上传。文件存储到服务器，但提供程序上的fileData对象始终返回空。代码如下。

 var url = "api/Documents/fileUpload";
                    var xhr = new XMLHttpRequest();
                    var file = document.getElementById("inputFile").files[0];
                    var formData = new FormData();
                    formData.append('file', file);
                    xhr.open("POST", url, true);
                    xhr.responseType = "text";
                    xhr.onreadystatechange = function () {
                        if (xhr.readyState == xhr.DONE) {
                            console.log("photoUpload xhr", xhr);
                            var responseTypeAsJSON = JSON.parse(xhr.responseText);
                            currentPhoto.responseText = xhr.responseText;
                            if (responseTypeAsJSON.result == "SUCCESS") {
                                currentPhoto.status = "SUCCESSfully uploaded";
                            }
                            else {
                                currentPhoto.status = responseTypeAsJSON.result;
                                alert(responseTypeAsJSON.message);
                            }
                            PhotoClear();
                            // console.log(currentPhoto);
                            // console.log("xhr done: ", xhr);  

                        }
                    }
                    xhr.send(formData);
                    // console.log("xhr sent: ", xhr);

接收控制器：

      [HttpPost]
    [ActionName("fileUpload")]
    public Task<HttpResponseMessage> fileUpload()
    {
        HttpRequestMessage request = this.Request;
        if (!request.Content.IsMimeMultipartContent())
        {
            throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
        }

        string root = System.Web.HttpContext.Current.Server.MapPath("~/App_Data");
        var provider = new MultipartFormDataStreamProvider(root);

        var task = request.Content.ReadAsMultipartAsync(provider).
            ContinueWith<HttpResponseMessage>(o =>
            {

                string file1 = provider.FileData.First().LocalFileName.ToString();
                // this is the file name on the server where the file was saved 

                return new HttpResponseMessage()
                {
                    Content = new StringContent("File uploaded.")
                };
            }
        );
        return task;
    }

以下是Chrome的请求。当我调试提供程序时，表单数据的键也是空的。然而，该文件被放入AppData

Request URL:http://localhost:4231/api/Documents/fileUpload
Request Headersview source
Content-Type:multipart/form-data; boundary=----WebKitFormBoundarycuGegdEDmBsR0mMl
Origin:http://localhost:4231
Referer:http://localhost:4231/
User-Agent:Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.22 (KHTML, like Gecko)     Chrome/25.0.1364.172 Safari/537.22
Request Payload
------WebKitFormBoundarycuGegdEDmBsR0mMl
Content-Disposition: form-data; name="testInfo"

some info here for testing
------WebKitFormBoundarycuGegdEDmBsR0mMl
Content-Disposition: form-data; name="file"; filename="irislogo.png"
Content-Type: image/png


------WebKitFormBoundarycuGegdEDmBsR0mMl--

Answer 1

我遇到了这个问题，一个小代码更改解决了这个问题。

该行：

 var provider = new MultipartFormDataStreamProvider(root);

应该是：

 var provider = new MultipartFileStreamProvider(root);

Answer 2

我也遇到过这个问题;这是解决方案：

public async Task<HttpResponseMessage> Save()
{
    string root = HttpContext.Current.Server.MapPath("~/App_Data");

    var provider = new MultipartFormDataStreamProvider(root);

    await Request.Content.ReadAsMultipartAsync(provider);

    // provider.FileData will contain your data...
    // you can also send form data which will be in provider.FormData
}

asp.net Web API文件上传fileData为空

2 个答案: