C# Signature:

[DllImport("shell32.dll")]
static extern uint SHFormatDrive(IntPtr hwnd, uint drive, uint fmtID,
   uint options);

User-Defined Types:

public enum SHFormatFlags : uint {
     SHFMT_ID_DEFAULT = 0xFFFF,
     SHFMT_OPT_FULL = 0x1,
     SHFMT_OPT_SYSONLY = 0x2,
     SHFMT_ERROR = 0xFFFFFFFF,
     SHFMT_CANCEL = 0xFFFFFFFE,
     SHFMT_NOFORMAT = 0xFFFFFFD,
}

Notes:

The hwnd field should be the handle of the required parent calling window (see http://msdn.microsoft.com/en-us/library/bb762169.aspx). passing in <parent window>.Handle (in C#) works in XP, but in Vista it does not. What works on Vista is passing in 0 (IntPtr.Zero). I have tested this on WP SP2 and it works there as well.

The fmtID field should always be passed SHFMT_ID_DEFAULT.

The drive field should denote the numerical listing of the drive letter to be formatted. (Ex: A is 0, Z is 25)

The options field should be 0 for a full disk format, pass SHFMT_OPT_FULL for a Quick Format, or set SHFMT_OPT_SYSONLY to create an MS-DOS System Boot Disk.

The function will return the ID of the last successful format, or one of the following error codes:

- SHFMT_ERROR: A general error occured while formatting. This is not an indication that the drive cannot be formatted though.

- SHFMT_CANCEL: The drive format was cancelled by user/OS.

- SHFMT_NOFORMAT: A serious error occured while formatting. The drive is unable to be formatted by the OS.

Tips & Tricks:

Please add some!

Sample Code:

C# Sample Call:

uint result = SHFormatDrive( this.Handle,
              2, // formatting C:
              (uint)SHFormatFlags.SHFMT_ID_DEFAULT,
              0 ); // full format of C:
if ( result == SHFormatFlags.SHFMT_ERROR )
    MessageBox.Show( "Unable to format the drive" );

NOTE- See the Note above about the hwnd field and Vista. Use

          SHFormatDrive( IntPtr.Zero,
              2, // formatting C:
              (uint)SHFormatFlags.SHFMT_ID_DEFAULT,
              0 ); // full format of C:

On Vista and better, you also have the Win32_Volume WMI classes.

Alternative Managed API:

Do you know one? Please contribute it!