如何在运行时设置HttpPostedFileBase ContentType值

Question

如何在运行时设置HttpPostedFileBase ContentType值？

    HttpPostedFileBase upl=null;
    string path="/exelFile/book1.xlsx";

    //-----Set Name Runtime 
    var Name="FileName.xlsx";
    //-----Set Type Runtime 
    var type="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";         
    byte[] bytes =System.IO.File.ReadAllBytes(Server.MapPath(Path));
    upl = (HttpPostedFileBase)new MemoryPostedFile(bytes, Name);

    //=====>how set type
    upl.ContentType 
    //==============

Answer 1

非常感谢@StephenMuecke。通过将'ContentType'添加到以下函数中解决了。

  public class MemoryPostedFile : HttpPostedFileBase
    {
        private readonly byte[] fileBytes;

        public MemoryPostedFile(byte[] fileBytes, string fileName = null,string ContentType=null)
        {
            this.fileBytes = fileBytes;
            this.FileName = fileName;
            this.ContentType = ContentType;
            this.InputStream = new MemoryStream(fileBytes);
        }

        public override int ContentLength => fileBytes.Length;

        public override string FileName { get; }

        public override string ContentType { get; }

        public override Stream InputStream { get; }
    }