C# webApi上传图片 代码篇

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代码篇，不多说

如下：

using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Threading.Tasks;
using System.Web.Http;

namespace FileUp.Controllers
{
    public class FileController : ApiController
    {
        [HttpPost]
        public async Task<string> UploadFileStream()
        {
            string returns = string.Empty;
            string fileType = "ss";//要创建的子文件夹的名字
            var uploadPath = "~/upload";
            string filePath = System.Web.HttpContext.Current.Server.MapPath(uploadPath + "/" + fileType + "/");//绝对路径
            //string filePath = uploadPath + "\\" + fileType + "\\";  //E:\Fileup  居家
            if (Directory.Exists(filePath) == false)
            {
                Directory.CreateDirectory(filePath);
            }

            try
            {
                var provider = new ReNameMultipartFormDataStreamProvider(filePath);

                await Request.Content.ReadAsMultipartAsync(provider).ContinueWith(o =>
                {

                    foreach (var file in provider.FileData)
                    {
                        string orfilename = file.Headers.ContentDisposition.FileName.TrimStart('"').TrimEnd('"');//待上传的文件名
                        FileInfo fileinfo = new FileInfo(file.LocalFileName);
                        //判断开始
                        int maxSize = ;
                        string oldName = orfilename;//选择的文件的名称
                        if (fileinfo.Length <= )
                        {
                            //文件大小判断 未选择上传的图片 大小为零
                        }
                        else if (fileinfo.Length > maxSize)
                        {
                            //文件大小判断 上传文件是否超限制
                        }
                        else
                        {
                            //
                            string fileExt = orfilename.Substring(orfilename.LastIndexOf('.'));
                            string Extension = fileExt;
                            string CreateTime = DateTime.Now.ToString("yyyyMMddHHmmss");

                            //定义允许上传的文件扩展名
                            String fileTypes = "gif,jpg,jpeg,png,bmp";
                            if (String.IsNullOrEmpty(fileExt) || Array.IndexOf(fileTypes.Split(','), fileExt.Substring().ToLower()) == -)
                            {

                                returns = "上传的文件格式不是图片";
                            }
                            else
                            {
                                returns = string.Format(@"/Uploads/{0}/{1}", fileType, System.IO.Path.GetFileName(file.LocalFileName));
                            }
                        }
                    }
                });
            }
            catch (Exception ex)
            {
                returns = ex.ToString();
            }
            return returns;
        }

        /// <summary>
        /// 重命名上传的文件
        /// </summary>
        public class ReNameMultipartFormDataStreamProvider : MultipartFormDataStreamProvider
        {
            public ReNameMultipartFormDataStreamProvider(string root)
                : base(root)
            { }

            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().Replace("-", "") + extension;
            }

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

        }
    }
}

PostMan请求如下：

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