/// <summary>
/// - "c:/dir1" + "dir2/file.txt" => "c:/dir1/dir2/file.txt"
/// - "c:/dir1" + "/from-root/file.txt" => "c:/from-root/file.txt"
/// - "c:/dir1" + "d:dir2/file.txt" (drive and relative path) => "d:/dir1/dir2/file.txt"
/// - "c:/dir1" + "\\.\server\share-name\dir2\file.txt" => "\\.\server\share-name\dir2\file.txt"
/// </summary>
/// <param name="aOther"></param>
/// <returns>new Filepath instance.</returns>
public Filepath Combine(string aOther)
{
if (string.IsNullOrEmpty(aOther))
{
return(this);
}
return(Combine(Filepath.Parse(aOther)));
}
/// <summary>
/// Traditional DOS path
/// Parse(@"C:\dir\file.txt");
/// Parse(@"relative\dir\and\file.txt");
/// Parse(@"\"); // root
/// Parse(@"C:\"); // drive and root
/// Parse(@"C:"); // specifies a drive, but relative
/// Parse(@"D:drive-and-relative\dir\file");
///
/// DOS Device path
/// Parse(@"\\?\volume/dir/more-dir/.git");
///
/// UNC path
/// Parse(@"\\server\share-name\dir\file");
///
/// UNIX
/// Parse("/usr/local/bin");
/// Parse("/"); // root
/// </summary>
/// <param name="aInput"></param>
/// <returns></returns>
public static Filepath Parse(string?aInput)
{
if (string.IsNullOrEmpty(aInput))
{
return(Empty);
}
var scan = new FilepathScanner(aInput ?? "");
var self = new Filepath();
self.Prefix = _ParsePrefix(scan);
self.Absolute = scan.Skip(SEPARATING_PATTERN);
self.Items = _ParsePath(scan).ToArray();
return(self);
}
public Filepath Combine(Filepath aOtherPath)
{
if (aOtherPath == null)
{
return(this);
}
return(new Filepath
{
Prefix = _SelectPrefix(aOtherPath.Prefix, this.Prefix),
Absolute = this.Absolute || aOtherPath.Absolute,
Items = aOtherPath.Absolute
? aOtherPath.Items
: this.Items.Concat(aOtherPath.Items).ToArray()
});
}
/// <summary>
/// 1. マイナスのstartは末尾からの距離と考え、1ステップだけ補正する
/// 2. マイナスのcountは、末尾からいくつ削るかの指定とみなす
/// 3. 大きなcountは補正する
/// 4. 補正後のstartが範囲外の場合はパスを空にする
/// </summary>
/// <param name="aStart">マイナス指定も可</param>
/// <param name="aCount">マイナス指定も可</param>
/// <returns></returns>
public Filepath Slice(int aStart, int aCount = int.MaxValue)
{
var rv = new Filepath
{
Prefix = this.Prefix,
};
var fixedHead = _FixHeadIndex(aStart);
var fixedTail = _FixTailIndex(fixedHead, aCount);
var fixedCount = fixedTail - fixedHead;
// 開始位置が 0 であれば、this.Absolute を踏襲。そうでなければ常に相対パスとなる
rv.Absolute = (fixedHead == 0) ? this.Absolute : false;
// countが1以上の場合のみ、Itemsを切り出して取得
rv.Items = (0 <= fixedHead) && (fixedHead < Items.Length) && (1 <= fixedCount)
? this.Items.Skip(fixedHead).Take(fixedCount).ToArray()
: _EMPTY;
return(rv);
}
