Code works not on Windows

[sloopidoopi]

The UNITY_EDITOR code doesn't work on Windows as Mono doesn't implemented the DriveInfo stuff.
Better use this solution(at least for Windows): http://stackoverflow.com/questions/1393711/get-free-disk-space

Here my changes:

public class DiskSpace
{

    #if UNITY_EDITOR_WIN || UNITY_STANDALONE_WIN
    //http://stackoverflow.com/questions/1393711/get-free-disk-space
    [DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
    [return: MarshalAs(UnmanagedType.Bool)]
    public static extern bool GetDiskFreeSpaceEx(string lpDirectoryName, out ulong lpFreeBytesAvailable, out ulong lpTotalNumberOfBytes, out ulong lpTotalNumberOfFreeBytes);

    #elif UNITY_ANDROID

    #elif UNITY_IPHONE
        [DllImport("__Internal")]
        private static extern long _iDiskSpace_FreeSpece(string path);
    #endif


    public static long FreeSpece {
        get
        {
        #if UNITY_EDITOR_WIN || UNITY_STANDALONE_WIN

  ulong free = 0, dummy1 = 0, dummy2 = 0;

            if (GetDiskFreeSpaceEx(Application.persistentDataPath, out free, out dummy1, out dummy2))
            {
                return (long)free;
            }

            #elif UNITY_ANDROID
                using(AndroidJavaObject statFs = new AndroidJavaObject( "android.os.StatFs", Application.persistentDataPath)) {
                    //statFs.getBlockSize() * statFs.getAvailableBlocks()
                    return statFs.Call<int>("getBlockSize") * statFs.Call<int>("getAvailableBlocks");
                }
            #elif UNITY_IPHONE
                return _iDiskSpace_FreeSpece(Application.persistentDataPath);
            #endif

            return -1;

}