class QDirListing¶

The QDirListing class provides an STL-style iterator for directory entries. More…

Added in version 6.8.

Synopsis¶

Methods¶

def __init__()
def __iter__()
def iteratorFlags()
def iteratorPath()
def nameFilters()
def swap()

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description¶

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

You can use QDirListing to navigate entries of a directory one at a time. It is similar to entryList() and entryInfoList() , but because it lists entries one at a time instead of all at once, it scales better and is more suitable for large directories. It also supports listing directory contents recursively, and following symbolic links. Unlike entryList() , QDirListing does not support sorting.

The QDirListing constructor takes a directory path string as argument. Here’s how to iterate over all entries recursively:

ItFlag = QDirListing.IteratorFlag()
for dirEntry in QDirListing("/etc", ItFlag::Recursive):
    print(dirEntry.filePath())
    # /etc/.
    # /etc/..
    # /etc/X11
    # /etc/X11/fs
    # ...

Here’s how to find and read all regular files filtered by name, recursively:

F = QDirListing.IteratorFlag()
def dirList("/sys",QStringList{"scaling_cur_freq"},F.Recursive):
for dirEntry in dirList:
    f = QFile(dirEntry.filePath())
    if f.open(QIODevice.ReadOnly):
        print(f.fileName(), f.readAll().trimmed().toDouble() / 1000, "MHz")

Here’s how to list only regular files, recursively:

F = QDirListing.IteratorFlag()
flags = F::FilesOnly | F::Recursive
for dirEntry in QDirListing("/etc", flags):
    # ...

Here’s how to list only regular files and symbolic links to regular files, recursively:

F = QDirListing.IteratorFlag()
flags = F::FilesOnly | F::Recursive | F::ResolveSymlinks
for dirEntry in QDirListing("/etc", flags):
    # ...

const_iterator models C++20 std::input_iterator , that is, it is a move-only, forward-only, single-pass iterator, that doesn’t allow random access. It can be used in ranged-for loops (or with C++20 range algorithms that don’t require random access iterators). Dereferencing a valid iterator returns a DirEntry object. The (c) end() sentinel marks the end of the iteration. Dereferencing an iterator that is equal to sentinel is undefined behavior.

DirEntry offers a subset of QFileInfo ‘s API (for example, fileName(), filePath(), exists()). Internally, DirEntry only constructs a QFileInfo object if needed, that is, if the info hasn’t been already fetched by other system functions. You can use fileInfo() to get a QFileInfo . For example:

ItFlag = QDirListing.IteratorFlag()
for dirEntry in QDirListing("/etc", ItFlag::Recursive):
    # Faster
    if dirEntry.fileName().endsWith(u".conf"):
    # This works, but might be potentially slower, since it has to construct a
    # QFileInfo, whereas (depending on the implementation) the fileName could
    # be known already
    if dirEntry.fileInfo().fileName().endsWith(u".conf"):
ItFlag = QDirListing.IteratorFlag()
for dirEntry in QDirListing("/etc", ItFlag::Recursive):
    # Both approaches are the same, because DirEntry will have to construct
    # a QFileInfo to get this info (for example, by calling system stat())
    if dirEntry.size() >= 4'000 /* 4KB */:
    if dirEntry.fileInfo().size() >= 4'000 /* 4KB */:

See also

QDir entryList()

class IteratorFlag¶

(inherits enum.Flag) This enum class describes flags that can be used to configure the behavior of QDirListing . Values from this enumerator can be bitwise OR’ed together.

Constant

Description

__init__(path[, flags=QDirListing.IteratorFlag.Default])¶

Parameters:

path – str
flags – Combination of IteratorFlag

Constructs a QDirListing that can iterate over path.

You can pass options via flags to control how the directory should be iterated.

By default, flags is Default .

See also

IteratorFlags

__init__(path, nameFilters[, flags=QDirListing.IteratorFlag.Default])

Parameters:

path – str
nameFilters – list of strings
flags – Combination of IteratorFlag

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

Constructs a QDirListing that can iterate over path.

You can pass options via flags to control how the directory should be iterated. By default, flags is Default .

The listed entries will be filtered according to the file glob patterns in nameFilters (see setNameFilters() for more details).

For example, the following iterator could be used to iterate over audio files:

QDirListing audioFileIt("/home/johndoe/", QStringList{"*.mp3", "*.wav"},
                        QDirListing.IteratorFlag.FilesOnly)