嘗試使用Web API POST txt文件，獲取415不支持的媒體類型

Question

進出口新的c#和目前正在設法POST幾個txt文件，使用Web API服務器，無法得到這個工作。 下面這個文章，我append荷蘭國際集團的文件formData和使用下面的代碼張貼：

public uploadMethod(formDataWithFiles) {
    return this.$http.post("/actionApi/Utils/UploadFile", formDataWithFiles).then((res) => {
        return res;
    }).catch((err) => {
        return err;
    });
}

這是應該接收文件並解析它們的后端代碼：

public async Task<HttpResponseMessage> UploadFile()
{
    if (!Request.Content.IsMimeMultipartContent())
    {
        return Request.CreateErrorResponse(HttpStatusCode.UnsupportedMediaType, "The request doesn't contain valid content!");
    }

    try
    {
        var provider = new MultipartMemoryStreamProvider();
        await Request.Content.ReadAsMultipartAsync(provider);
        foreach (var file in provider.Contents)
        {
            var dataStream = await file.ReadAsStreamAsync();
            // use the data stream to persist the data to the server (file system etc)

            var response = Request.CreateResponse(HttpStatusCode.OK);
            response.Content = new StringContent("Successful upload", Encoding.UTF8, "text/plain");
            response.Content.Headers.ContentType = new MediaTypeWithQualityHeaderValue(@"text/html");
            return response;
        }
        return Request.CreateErrorResponse(HttpStatusCode.InternalServerError,"problem.");

    }
    catch (Exception e)
    {
        return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, e.Message);
    }
}

我得到的例外：

加載資源失敗：服務器響應狀態為415（不支持的媒體類型）

要求正文：

General:

    Request URL: http://localhost:48738/actionApi/Utils/UploadFile
    Referrer Policy: no-referrer-when-downgrade

Request Headers:
Provisional headers are shown
Accept: application/json, text/plain, */*
Authorization: Bearer _en....
Origin: http://localhost:48738
Referer: http://localhost:48738/
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 

(KHTML, like Gecko) Chrome/66.0.3359.181 Safari/537.36

Request Patload:
------WebKitFormBoundaryYAuasRL66eAdhUtd
Content-Disposition: form-data; name="34.txt"; filename="34.txt"
Content-Type: text/plain


------WebKitFormBoundaryYAuasRL66eAdhUtd
Content-Disposition: form-data; name="35.txt"; filename="35.txt"
Content-Type: text/plain

Answer 1

根據您的響應，http標頭的Content-Type不正確，應改為Content-Type: multipart/form-data

這可能是由您的Javascript代碼引起的，所以請使用以下代碼作為如何為angularJS觸發文件上傳ajax的示例

 var filedata = $("#fileupload").prop("files")[0]; var formData = new FormData(); formData.append("file", filedata); var uploadUrl = "/actionApi/Utils/UploadFile"; uploadMethod(uploadUrl, formData); function uploadMethod(uploadUrl, form_data) { $http .post(uploadUrl, form_data, { transformRequest: angular.identity, headers: { "Content-Type": undefined } }) .success(function() {}) .error(function() {}); }