WebAPI文件上传与下载

项目预览：

webApi文件上传与下载
支持多文件批量上传
文件在服务器端以GUID重命名存储
上传后返回文件信息

上传接口控制器：

public class FilesController : ApiController
    {
        public IEnumerable<string> Get()
        {
            return new string[] { "value1", "value2" };
        }

        private const string UploadFolder = "uploads";

        public HttpResponseMessage Get(string fileName)
        {
            HttpResponseMessage result = null;

            DirectoryInfo directoryInfo = new DirectoryInfo(HostingEnvironment.MapPath("~/App_Data/" + UploadFolder));
            FileInfo foundFileInfo = directoryInfo.GetFiles().Where(x => x.Name == fileName).FirstOrDefault();
            if (foundFileInfo != null)
            {
                FileStream fs = new FileStream(foundFileInfo.FullName, FileMode.Open);

                result = new HttpResponseMessage(HttpStatusCode.OK);
                result.Content = new StreamContent(fs);
                result.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/octet-stream");
                result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
                result.Content.Headers.ContentDisposition.FileName = foundFileInfo.Name;
            }
            else
            {
                result = new HttpResponseMessage(HttpStatusCode.NotFound);
            }

            return result;
        }

        public Task<IQueryable<HDFile>> Post()
        {
            try
            {
                //uploadFolderPath variable determines where the files should be temporarily uploaded into server. 
                //Remember to give full control permission to IUSER so that IIS can write file to that folder.
                string uploadFolderPath = HostingEnvironment.MapPath("~/App_Data/" + UploadFolder);

                //如果路径不存在，创建路径
                if (!Directory.Exists(uploadFolderPath))
                    Directory.CreateDirectory(uploadFolderPath);

                //#region CleaningUpPreviousFiles.InDevelopmentOnly
                //DirectoryInfo directoryInfo = new DirectoryInfo(uploadFolderPath);
                //foreach (FileInfo fileInfo in directoryInfo.GetFiles())
                //	fileInfo.Delete();
                //#endregion

                if (Request.Content.IsMimeMultipartContent()) //If the request is correct, the binary data will be extracted from content and IIS stores files in specified location.
                {
                    var streamProvider = new WithExtensionMultipartFormDataStreamProvider(uploadFolderPath);
                    var task = Request.Content.ReadAsMultipartAsync(streamProvider).ContinueWith<IQueryable<HDFile>>(t =>
                    {
                        if (t.IsFaulted || t.IsCanceled)
                        {
                            throw new HttpResponseException(HttpStatusCode.InternalServerError);
                        }

                        var fileInfo = streamProvider.FileData.Select(i =>
                        {
                            var info = new FileInfo(i.LocalFileName);
                            return new HDFile(info.Name, string.Format("{0}?filename={1}", Request.RequestUri.AbsoluteUri, info.Name), (info.Length / 1024).ToString());
                        });
                        return fileInfo.AsQueryable();
                    });

                    return task;
                }
                else
                {
                    throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.NotAcceptable, "This request is not properly formatted"));
                }
            }
            catch (Exception ex)
            {
                throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.BadRequest, ex.Message));
            }
        }


        public class HDFile
        {
            public HDFile(string name, string url, string size)
            {
                Name = name;
                Url = url;
                Size = size;
            }

            public string Name { get; set; }

            public string Url { get; set; }

            public string Size { get; set; }
        }

    }

  public class WithExtensionMultipartFormDataStreamProvider : MultipartFormDataStreamProvider
    {
        public WithExtensionMultipartFormDataStreamProvider(string rootPath)
            : base(rootPath)
        {
        }

        public override string GetLocalFileName(System.Net.Http.Headers.HttpContentHeaders headers)
        {
            string extension = !string.IsNullOrWhiteSpace(headers.ContentDisposition.FileName) ? Path.GetExtension(GetValidFileName(headers.ContentDisposition.FileName)) : "";
            return Guid.NewGuid().ToString() + extension;
        }

        private string GetValidFileName(string filePath)
        {
            char[] invalids = System.IO.Path.GetInvalidFileNameChars();
            return String.Join("_", filePath.Split(invalids, StringSplitOptions.RemoveEmptyEntries)).TrimEnd('.');
        }
    }

客户端

界面:

public class ServerFileHelper
    {
        private readonly string api = "http://localhost:6841/api/files";

        public ServerFileHelper(string apiurl)
        {
            api = apiurl;
        }
        public IEnumerable<HDFile> UploadFiles(params string[] FullFileNames)
        {
            Uri server = new Uri(api);
            HttpClient httpClient = new HttpClient();

            MultipartFormDataContent multipartFormDataContent = new MultipartFormDataContent();

            foreach (string fullfilename in FullFileNames)
            {
                string filename = Path.GetFileName(fullfilename);
                string filenameWithoutExtension = Path.GetFileNameWithoutExtension(fullfilename);
                //这里会向服务器上传一个png图片和一个txt文件
                StreamContent streamConent = new StreamContent(new FileStream(fullfilename, FileMode.Open, FileAccess.Read, FileShare.Read));

                multipartFormDataContent.Add(streamConent, filenameWithoutExtension, filename);
            }

            HttpResponseMessage responseMessage = httpClient.PostAsync(server, multipartFormDataContent).Result;

            if (responseMessage.IsSuccessStatusCode)
            {
                IList<HDFile> hdFiles=null;

                string content = responseMessage.Content.ReadAsStringAsync().Result;
                hdFiles = Newtonsoft.Json.JsonConvert.DeserializeObject<IList<HDFile>>(content);

                if (hdFiles.Count > 0)
                    return hdFiles;
                else
                    return null;


            }
            return null;
        }

        public bool DownLoad(string ServerFileName, string SaveFileName)
        {
            Uri server = new Uri(String.Format("{0}?filename={1}", api, ServerFileName));
            HttpClient httpClient = new HttpClient();

            string p = Path.GetDirectoryName(SaveFileName);

            if (!Directory.Exists(p))
                Directory.CreateDirectory(p);

            HttpResponseMessage responseMessage = httpClient.GetAsync(server).Result;

            if (responseMessage.IsSuccessStatusCode)
            {
                using (FileStream fs = File.Create(SaveFileName))
                {
                    Stream streamFromService = responseMessage.Content.ReadAsStreamAsync().Result;
                    streamFromService.CopyTo(fs);
                    return true;
                }
            }
            else
                return false;
        }
    }

git项目源码地址:

https://github.com/GarsonZhang/FileUpLoadAPI