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class function IsExtendedPrefixed(const Path: string): Boolean; inline; static;


static bool __fastcall IsExtendedPrefixed(const System::UnicodeString Path);


Type Visibility Source Unit Parent
function public
System.IOUtils TPath


Checks whether a given path has an extended prefix.

Call IsExtendedPrefixed to check whether the given path contains an extension prefix.

Paths prefixed with \\?\ or \\?\UNC\ are Windows-specific and can be of very big lengths and not restricted to 255 characters (MAX_PATH). It is a common case today to manage paths longer than 255 characters. Prefixing those with \\?\ solves the problem.

For example, in file I/O, the \\?\ tells the Windows APIs to disable all string parsing and to send the string that follows it to the file system. Therefore, you can exceed the MAX_PATH limits that are enforced by Windows APIs.

On POSIX, IsExtendedPrefixed always returns false, since there are no extended prefixes.

See Also