Static Functions

QVariant parse(const QString &value)

Try to convert a given value to a QPointF, QRectF, int or float.

function definition:

static QVariant parse(const QString &value);

parameters:

Parameter Type Description

value const QString & String value to be converted.
output: (QVariant) The converted file if a conversion was possible. Otherwise the unconverted string is returned.

example:

QString point = "(1, 1)";
QString rect = "(1, 1, 5, 5)";
QString integer = "1";
QString fp = "1.0";
QString string = "Hello World";

File::parse(point);   // returns QVariant(QPointF, QPointF(1, 1))
File::parse(rect);    // returns QVariant(QRectF, QRectF(1, 1, 5x5))
File::parse(integer); // returns QVariant(int, 1)
File::parse(fp);      // returns QVariant(float, 1.0f)
File::parse(string);  // returns QVariant(QString, "Hello World")

QList<QVariant> values(const QList<U> &fileList, const QString &key)

Gather a list of QVariant values associated with a metadata key from a provided list of files.

function definition:

template<class U> static [QList<QVariant> values(const QList<U> &fileList, const QString &key)

parameters:

Parameter	Type	Description
fileList	const QList<U> &	A list of files to parse for values. A type is required for `U`. Valid options are: File QString
key	const QString &	A metadata key used to lookup the values.

output: (QList<QVariant>) A list of QVariant values associated with the given key in each of the provided files.

example:

File f1, f2;
f1.set("Key1", QVariant::fromValue<float>(1));
f1.set("Key2", QVariant::fromValue<float>(2));
f2.set("Key1", QVariant::fromValue<float>(3));

File::values<File>(QList<File>() << f1 << f2, "Key1"); // returns [QVariant(float, 1),
                                                       //          QVariant(float, 3)]

QList<T> get(const QList<U> &fileList, const QString &key)

Gather a list of T values associated with a metadata key from a provided list of files. T is a user provided type. If the key does not exist in the metadata of any file an error is thrown.

function definition:

template<class T, class U> static QList<T> get(const QList<U> &fileList, const QString &key)

parameters:

Parameter	Type	Description
fileList	const QList<U> &	A list of files to parse for values. A type is required for U. Valid options are: File QString
key	const QString &	A metadata key used to lookup the values.

output: (QList<T>) A list of the values of type T associated with the given key. A type is required for T.

example:

File f1, f2;
f1.set("Key1", QVariant::fromValue<float>(1));
f1.set("Key2", QVariant::fromValue<float>(2));
f2.set("Key1", QVariant::fromValue<float>(3));

File::get<float, File>(QList<File>() << f1 << f2, "Key1");  // returns [1., 3.]
File::get<float, File>(QList<File>() << f1 << f2, "Key2");  // Error: Key doesn't exist in f2
File::get<QRectF, File>(QList<File>() << f1 << f2, "Key1"); // Error: float is not convertable to QRectF

QList<T> get(const QList<U> &fileList, const QString &key, const T &defaultValue)

Gather a list of T values associated with a metadata key from a provided list of files. T is a user provided type. If the key does not exist in the metadata of any file the provided defaultValue is used.

function definition:

template<class T, class U> static QList<T> get(const QList<U> &fileList, const QString &key, const T &defaultValue)

parameters:

Parameter	Type	Description
fileList	const QList<U> &	A list of files to parse for values. A type is required for U. Valid options are: File QString
key	const QString &	A metadata key used to lookup the values.
defaultValue	const T &	The default value if the key is not in a file's metadata. A type is required for T. All types are valid.

output: (QList<T>) A list of the values of type T associated with the given key. A type is required for T.
example:

File f1, f2; f1.set("Key1", QVariant::fromValue(1)); f1.set("Key2", QVariant::fromValue(2)); f2.set("Key1", QVariant::fromValue(3));

File::get(QList() << f1 << f2, "Key1"); // returns [1., 3.] File::get(QList() << f1 << f2, "Key2", QList() << 1); // returns [1.] File::get(QList() << f1 << f2, "Key1, QList()"); // returns []

QDebug operator <<(QDebug dbg, const File &file)

Calls flat on the given file and then streams that file to stderr.

function definition:

QDebug operator <<(QDebug dbg, const File &file)

parameter:

Parameter Type Description

dbg QDebug The debug stream

file const File & File to stream
output: (QDebug &) returns a reference to the updated debug stream

example:

File file("../path/to/pictures/picture.jpg");
file.set("Key", QString("Value"));

qDebug() << file; // "../path/to/pictures/picture.jpg[Key=Value]" streams to stderr

QDataStream &operator <<(QDataStream &stream, const File &file)

Serialize a file to a data stream.

function definition:

QDataStream &operator <<(QDataStream &stream, const File &file)

parameters:

Parameter Type Description

stream QDataStream The data stream

file const File & File to stream
output: (QDataStream &) returns a reference to the updated data stream

example:

void store(QDataStream &stream)
{
    File file("../path/to/pictures/picture.jpg");
    file.set("Key", QString("Value"));

    stream << file; // "../path/to/pictures/picture.jpg[Key=Value]" serialized to the stream
}

QDataStream &operator >>(QDataStream &stream, const File &file)

Deserialize a file from a data stream.

function definition:

QDataStream &operator >>(QDataStream &stream, const File &file)

parameters:

Parameter Type Description

stream QDataStream The data stream

file const File & File to stream
output: (QDataStream &) returns a reference to the updated data stream

example:

void load(QDataStream &stream)
{
    File in("../path/to/pictures/picture.jpg");
    in.set("Key", QString("Value"));

    stream << in; // "../path/to/pictures/picture.jpg[Key=Value]" serialized to the stream

    File out;
    stream >> out;

    out.name; // returns "../path/to/pictures/picture.jpg"
    out.flat(); // returns "../path/to/pictures/picture.jpg[Key=Value]"
}