该进程无法访问文件XXX，因为它正在由asp.net web api中的另一个进程使用

Question

我开发了ASP.NET Web API。我试图读取excel文件的内容并尝试将其作为字节返回。我收到了以下错误：

The process cannot access the file 'C:\app\MyHost.AppServices\bin\Debug\temp\888.xlsx' because it is being used by another process.

我正在使用下面的代码。我不确定是什么导致了这个错误。请提供您的建议

public class FileController : MyBase
    {
        public HttpResponseMessage Get(string id)
        {


            if (String.IsNullOrEmpty(id))
                return Request.CreateResponse(HttpStatusCode.BadRequest);
            var path = Path.Combine("temp", id);
            var fileStream = File.Open(path, FileMode.Open);
            HttpResponseMessage response = new HttpResponseMessage(HttpStatusCode.OK);
            //response.Content = new StreamContent(fileStream);


            response.Content = new StreamContent(new FileStream(path, FileMode.Open, FileAccess.ReadWrite));
            response.Content.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("attachment");
            response.Content.Headers.ContentDisposition.FileName = id;

            return response;

            }
    }

Answer 1

您永远不会从var fileStream = File.Open(path, FileMode.Open);处置文件，而是将其锁定。