- Без учета регистра
- Допускает сочетание
\ и / разделителей папок - Допускает
..\ в пути - Избегает совпадения при частичных именах папок(
c:\foobar не подпуть c:\foo)
Примечание. Это соответствует только строке пути и не работает для символических ссылок и ссылок других типов в файловой системе.
Код:
public static class StringExtensions
{
/// <summary>
/// Returns true if <paramref name="path"/> starts with the path <paramref name="baseDirPath"/>.
/// The comparison is case-insensitive, handles / and \ slashes as folder separators and
/// only matches if the base dir folder name is matched exactly ("c:\foobar\file.txt" is not a sub path of "c:\foo").
/// </summary>
public static bool IsSubPathOf(this string path, string baseDirPath)
{
string normalizedPath = Path.GetFullPath(path.Replace('/', '\\')
.WithEnding("\\"));
string normalizedBaseDirPath = Path.GetFullPath(baseDirPath.Replace('/', '\\')
.WithEnding("\\"));
return normalizedPath.StartsWith(normalizedBaseDirPath, StringComparison.OrdinalIgnoreCase);
}
/// <summary>
/// Returns <paramref name="str"/> with the minimal concatenation of <paramref name="ending"/> (starting from end) that
/// results in satisfying .EndsWith(ending).
/// </summary>
/// <example>"hel".WithEnding("llo") returns "hello", which is the result of "hel" + "lo".</example>
public static string WithEnding([CanBeNull] this string str, string ending)
{
if (str == null)
return ending;
string result = str;
// Right() is 1-indexed, so include these cases
// * Append no characters
// * Append up to N characters, where N is ending length
for (int i = 0; i <= ending.Length; i++)
{
string tmp = result + ending.Right(i);
if (tmp.EndsWith(ending))
return tmp;
}
return result;
}
/// <summary>Gets the rightmost <paramref name="length" /> characters from a string.</summary>
/// <param name="value">The string to retrieve the substring from.</param>
/// <param name="length">The number of characters to retrieve.</param>
/// <returns>The substring.</returns>
public static string Right([NotNull] this string value, int length)
{
if (value == null)
{
throw new ArgumentNullException("value");
}
if (length < 0)
{
throw new ArgumentOutOfRangeException("length", length, "Length is less than zero");
}
return (length < value.Length) ? value.Substring(value.Length - length) : value;
}
}
Контрольные примеры (NUnit):
[TestFixture]
public class StringExtensionsTest
{
[TestCase(@"c:\foo", @"c:", Result = true)]
[TestCase(@"c:\foo", @"c:\", Result = true)]
[TestCase(@"c:\foo", @"c:\foo", Result = true)]
[TestCase(@"c:\foo", @"c:\foo\", Result = true)]
[TestCase(@"c:\foo\", @"c:\foo", Result = true)]
[TestCase(@"c:\foo\bar\", @"c:\foo\", Result = true)]
[TestCase(@"c:\foo\bar", @"c:\foo\", Result = true)]
[TestCase(@"c:\foo\a.txt", @"c:\foo", Result = true)]
[TestCase(@"c:\FOO\a.txt", @"c:\foo", Result = true)]
[TestCase(@"c:/foo/a.txt", @"c:\foo", Result = true)]
[TestCase(@"c:\foobar", @"c:\foo", Result = false)]
[TestCase(@"c:\foobar\a.txt", @"c:\foo", Result = false)]
[TestCase(@"c:\foobar\a.txt", @"c:\foo\", Result = false)]
[TestCase(@"c:\foo\a.txt", @"c:\foobar", Result = false)]
[TestCase(@"c:\foo\a.txt", @"c:\foobar\", Result = false)]
[TestCase(@"c:\foo\..\bar\baz", @"c:\foo", Result = false)]
[TestCase(@"c:\foo\..\bar\baz", @"c:\bar", Result = true)]
[TestCase(@"c:\foo\..\bar\baz", @"c:\barr", Result = false)]
public bool IsSubPathOfTest(string path, string baseDirPath)
{
return path.IsSubPathOf(baseDirPath);
}
}
Обновления
- 2015-08-18: исправление ошибок в неполной папкеимена.Добавить тестовые случаи.
- 2015-09-02: Поддержка
..\ в путях, добавить отсутствующий код - 2017-09-06: Добавить примечание к символическим ссылкам.