QFileInfo

QFileInfo is a lightweight, value-based class in the QtCore module of the Qt framework. It provides information about files and directories without opening them, encapsulating a filesystem path and exposing metadata such as existence, type, name components, size, timestamps, and permissions. QFileInfo can also resolve canonical or symlink targets where supported by the platform.

Construction and basic usage: QFileInfo can be created from a path string, from a QDir and a file name, or from a QFile object. Common constructors include a default constructor, QFileInfo(const QString &file), and QFileInfo(const QDir &dir, const QString &fileName). This enables convenient creation from various sources within Qt-based applications.

Path and name queries: Methods such as filePath(), absoluteFilePath(), canonicalFilePath(), path() and fileName() provide the full path and file name components. baseName() returns the file name without its suffix, while suffix() returns the last suffix and completeSuffix() returns the full suffix (for example, "tar.gz" for "archive.tar.gz").

Status and metadata: Key capabilities include exists(), isDir(), isFile(), and isSymLink() to determine the object type. Optional boolean checks like isExecutable(), isReadable(), and isWritable() reflect the file’s permissions. Size information is available via size(). Timestamps such as created(), lastModified(), and lastRead() give the corresponding moments. For symbolic links, symLinkTarget() can reveal the link’s target.

Platform behavior and integration: QFileInfo delegates to the underlying operating system to retrieve metadata and is commonly used with other Qt I/O classes (notably QFile) to inspect objects before performing read, write, or copy operations. It is a non-graphical, cross-platform utility that aids in robust file-system handling.