| Directory | System.IO | Static helpers for directory management — create, delete, enumerate, get current directory. |
| DirectoryInfo | System.IO | |
| DriveInfo | System.IO | Information about a mounted volume — total/available space, type, root path. |
| File | System.IO | |
| FileEnum | System.IO | |
| FileEnumerator | System.IO | |
| FileInfo | System.IO | |
| FileStream | System.IO | A read/write stream backed by a file on a mounted file system. Construct via File.OpenRead(string) / File.OpenWrite(string) / File.Create(string). |
| FileSystem | GHIElectronics.TinyCLR.IO | Mounts and unmounts file systems on top of a GHIElectronics.TinyCLR.Devices.Storage.StorageController. Pass the controller's Hdc to Mount(IntPtr) to make its content accessible via System.IO.File / System.IO.Directory. |
| FileSystemEntry | GHIElectronics.TinyCLR.IO | |
| FileSystemInfo | System.IO | |
| Path | System.IO | |
| TextReader | System.IO | |
| TextWriter | System.IO | |