web api 文件管理器(含文件上传以及MD5特征标志)

【核心代码】

using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Threading.Tasks;
using System.Web;
using System.Web.Http;
using System.Web.Http.Description;
using WebResource.Models;

namespace WebResource.Controllers
{
    [RoutePrefix("Res")]
    public class ResourceApiController : ApiController
    {
        private WebResourceContext db = new WebResourceContext();
        private static readonly long MEMORY_SIZE = 64 * 1024 * 1024;
        private static readonly string ROOT_PATH = HttpContext.Current.Server.MapPath("~/App_Data/");

        /// <summary>
        /// Post File
        /// </summary>
        /// <param name="Id">Md5</param>
        /// <returns>Resource</returns>
        [HttpPost]
        [Route("Upload/{Id?}")]
        [ResponseType(typeof(Resource))]
        public async Task<IHttpActionResult> Post(string Id = null)
        {
            List<Resource> resources = new List<Resource>();

            // multipart/form-data
            var provider = new MultipartMemoryStreamProvider();
            await Request.Content.ReadAsMultipartAsync(provider);

            foreach (var item in provider.Contents)
            {
                if (item.Headers.ContentDisposition.FileName != null)
                {
                    //Strem
                    var ms = item.ReadAsStreamAsync().Result;

                    using (var br = new BinaryReader(ms))
                    {
                        if (ms.Length <= 0)
                            break;
                        var data = br.ReadBytes((int)ms.Length);
                        //Md5
                        string id = HashUtils.GetMD5Hash(data);

                        Resource temp = await db.Resources.FindAsync(id);
                        if (temp == null)
                        {
                            //Create
                            Resource resource = new Resource();
                            resource.Id = id;
                            resource.Size = ms.Length;
                            resource.Cursor = resource.Size;
                            resource.Published = DateTime.Now;
                            //Info
                            FileInfo info = new FileInfo(item.Headers.ContentDisposition.FileName.Replace("\"", ""));
                            resource.Type = info.Extension.Substring(1).ToLower();
                            resource.Name = info.Name.Substring(0, info.Name.LastIndexOf("."));
                            //Relative
                            resource.Folder = DateTime.Now.ToString("yyyyMM/dd/", DateTimeFormatInfo.InvariantInfo);

                            //Write
                            try
                            {
                                string dirPath = Path.Combine(ROOT_PATH, resource.Folder);
                                if (!Directory.Exists(dirPath))
                                {
                                    Directory.CreateDirectory(dirPath);
                                }

                                File.WriteAllBytes(Path.Combine(dirPath, resource.Id), data);
                                //Save To Datebase
                                db.Resources.Add(resource);
                                await db.SaveChangesAsync();
                                temp = await db.Resources.FindAsync(resource.Id);
                            }
                            catch { }
                        }
                        if (temp != null)
                            resources.Add(temp);
                    }
                }
            }

            if (resources.Count == 0)
                return BadRequest();
            else if (resources.Count == 1)
                return Ok(resources.FirstOrDefault());
            else
                return Ok(resources);
        }
    }
}