如何对FileInfo []中的文件进行排序，然后将硬盘中的最后一个Gif文件从FileInfo []分配给pictureBox1？

Question

path_exe = Path.GetDirectoryName(Application.LocalUserAppDataPath);
radarImagesDirectory = Path.Combine(path_exe, radarImagesDirectory);
dirinfo = new DirectoryInfo(radarImagesDirectory);
fileinfo = dirinfo.GetFiles("*.gif");
Bitmap bmp = new Bitmap(fileinfo[fileinfo.Length - 1].Name);
pictureBox1.Image = bmp;

In fileinfo i see about 10000 files gif files. They start from 0 to 10000 but is it real sorted like that ? If i will display file 10000 is it realy the last file or need some how to sort the fileinfo first ?

And i did Bitmap bmp = new Bitmap(fileinfo[fileinfo.Length - 1].Name); i wanted to display in the pictureBox1 the last gif file but i'm getting exception on this line:

Parameter is not valid

System.ArgumentException was unhandled
  HResult=-2147024809
  Message=Parameter is not valid.
  Source=System.Drawing
  StackTrace:
       at System.Drawing.Bitmap..ctor(String filename)
       at Weather_Radar.Form1..ctor() in d:\C-Sharp\Weather Radar\Weather Radar\Weather Radar\Form1.cs:line 47
       at Weather_Radar.Program.Main() in d:\C-Sharp\Weather Radar\Weather Radar\Weather Radar\Program.cs:line 19
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: 

Answer 1

Something like this should help you out:

var ordered = dirinfo.EnumerateFiles("*.gif")
                     .OrderByDescending(f => f.LastWriteTime);
FileInfo newest = ordered.FirstOrDefault();
FileInfo oldest = ordered.LastOrDefault();

Image img1 = Image.FromFile(newest.FullName);
// etc etc

(Remembering to include using System.Linq; )