QUrlOperator(3qt)QUrlOperator(3qt)NAME
QUrlOperator - Common operations on URLs
SYNOPSIS
#include <qurloperator.h>
Inherits QObject and QUrl.
Public Members
QUrlOperator ()
QUrlOperator ( const QString & url )
QUrlOperator ( const QUrlOperator & url )
QUrlOperator ( const QUrlOperator & url, const QString & relUrl, bool
checkSlash = FALSE )
virtual ~QUrlOperator ()
virtual const QNetworkOperation * listChildren ()
virtual const QNetworkOperation * mkdir ( const QString & dirname )
virtual const QNetworkOperation * remove ( const QString & filename )
virtual const QNetworkOperation * rename ( const QString & oldname,
const QString & newname )
virtual const QNetworkOperation * get ( const QString & location =
QString::null )
virtual const QNetworkOperation * put ( const QByteArray & data, const
QString & location = QString::null )
virtual QPtrList<QNetworkOperation> copy ( const QString & from, const
QString & to, bool move = FALSE, bool toPath = TRUE )
virtual void copy ( const QStringList & files, const QString & dest,
bool move = FALSE )
virtual bool isDir ( bool * ok = 0 )
virtual void setNameFilter ( const QString & nameFilter )
QString nameFilter () const
virtual QUrlInfo info ( const QString & entry ) const
virtual void stop ()
Signals
void newChildren ( const QValueList<QUrlInfo> & i, QNetworkOperation *
op )
void finished ( QNetworkOperation * op )
void start ( QNetworkOperation * op )
void createdDirectory ( const QUrlInfo & i, QNetworkOperation * op )
void removed ( QNetworkOperation * op )
void itemChanged ( QNetworkOperation * op )
void data ( const QByteArray & data, QNetworkOperation * op )
void dataTransferProgress ( int bytesDone, int bytesTotal,
QNetworkOperation * op )
void startedNextCopy ( const QPtrList<QNetworkOperation> & lst )
void connectionStateChanged ( int state, const QString & data )
Protected Members
virtual void clearEntries ()
void getNetworkProtocol ()
void deleteNetworkProtocol ()
RELATED FUNCTION DOCUMENTATION
void qInitNetworkProtocols ()
DESCRIPTION
The QUrlOperator class provides common operations on URLs.
This class operates on hierarchical structures (such as filesystems)
using URLs. Its API facilitates all the common operations: <center>.nf
</center>
You can obtain additional information about the URL with isDir() and
info(). If a directory is to be traversed using listChildren(), a name
filter can be set with setNameFilter().
A QUrlOperator can be used like this, for example to download a file
(and assuming that the FTP protocol is registered):
QUrlOperator *op = new QUrlOperator();
op->copy( QString("ftp://ftp.trolltech.com/qt/source/qt-2.1.0.tar.gz"),
"file:/tmp" );
If you want to be notified about success/failure, progress, etc., you
can connect to QUrlOperator's signals, e.g. to start(), newChildren(),
createdDirectory(), removed(), data(), dataTransferProgress(),
startedNextCopy(), connectionStateChanged(), finished(), etc. A network
operation can be stopped with stop().
The class uses the functionality of registered network protocols to
perform these operations. Depending of the protocol of the URL, it uses
an appropriate network protocol class for the operations. Each of the
operation functions of QUrlOperator creates a QNetworkOperation object
that describes the operation and puts it into the operation queue for
the network protocol used. If no suitable protocol could be found
(because no implementation of the necessary network protocol is
registered), the URL operator emits errors. Not every protocol supports
every operation, but error handling deals with this problem.
To register the available network protocols, use the
qInitNetworkProtocols() function. The protocols currently supported
are:
FTP,
HTTP,
local file system.
For more information about the Qt Network Architecture see the Qt
Network Documentation.
See also QNetworkProtocol, QNetworkOperation, Input/Output and
Networking, and Miscellaneous Classes.
MEMBER FUNCTION DOCUMENTATIONQUrlOperator::QUrlOperator ()
Constructs a QUrlOperator with an empty (i.e. invalid) URL.
QUrlOperator::QUrlOperator ( const QString & url )
Constructs a QUrlOperator using url and parses this string.
If you pass strings like "/home/qt" the "file" protocol is assumed.
QUrlOperator::QUrlOperator ( const QUrlOperator & url )
Constructs a copy of url.
QUrlOperator::QUrlOperator ( const QUrlOperator & url, const QString & relUrl,
bool checkSlash = FALSE )
Constructs a QUrlOperator. The URL on which this QUrlOperator operates
is constructed out of the arguments url, relUrl and checkSlash: see the
corresponding QUrl constructor for an explanation of these arguments.
QUrlOperator::~QUrlOperator () [virtual]
Destructor.
void QUrlOperator::clearEntries () [virtual protected]
Clears the cache of children.
void QUrlOperator::connectionStateChanged ( int state, const QString & data )
[signal]
This signal is emitted whenever the URL operator's connection state
changes. state describes the new state, which is a
QNetworkProtocol::ConnectionState value.
data is a string that describes the change of the connection. This can
be used to display a message to the user.
QPtrList<QNetworkOperation> QUrlOperator::copy ( const QString & from, const
QString & to, bool move = FALSE, bool toPath = TRUE ) [virtual]
Copies the file from to to. If move is TRUE, the file is moved (copied
and removed). from must point to a file and to must point to a
directory (into which from is copied) unless toPath is set to FALSE. If
toPath is set to FALSE then the to variable is assumed to be the
absolute file path (destination file path + file name). The copying is
done using the get() and put() operations. If you want to be notified
about the progress of the operation, connect to the
dataTransferProgress() signal. Bear in mind that the get() and put()
operations emit this signal through the QUrlOperator. The number of
transferred bytes and the total bytes that you receive as arguments in
this signal do not relate to the the whole copy operation; they relate
first to the get() and then to the put() operation. Always check what
type of operation the signal comes from; this is given in the signal's
last argument.
At the end, finished() (with success or failure) is emitted, so check
the state of the network operation object to see whether or not the
operation was successful.
Because a move or copy operation consists of multiple operations
(get(), put() and maybe remove()), this function doesn't return a
single QNetworkOperation, but rather a list of them. They are in the
order: get(), put() and (if applicable) remove().
See also get() and put().
void QUrlOperator::copy ( const QStringList & files, const QString & dest,
bool move = FALSE ) [virtual]
This is an overloaded member function, provided for convenience. It
behaves essentially like the above function.
Copies the files to the directory dest. If move is TRUE the files are
moved, not copied. dest must point to a directory.
This function calls copy() for each entry in files in turn. You don't
get a result from this function; each time a new copy begins,
startedNextCopy() is emitted, with a list of QNetworkOperations that
describe the new copy operation.
void QUrlOperator::createdDirectory ( const QUrlInfo & i, QNetworkOperation *
op ) [signal]
This signal is emitted when mkdir() succeeds and the directory has been
created. i holds the information about the new directory.
op is a pointer to the operation object, which contains all the
information about the operation, including the state. op->arg(0) holds
the new directory's name.
See also QNetworkOperation and QNetworkProtocol.
void QUrlOperator::data ( const QByteArray & data, QNetworkOperation * op )
[signal]
This signal is emitted when new data has been received after calling
get() or put(). op is a pointer to the operation object which contains
all the information about the operation, including the state.
op->arg(0) holds the name of the file whose data is retrieved and
op->rawArg(1) holds the (raw) data.
See also QNetworkOperation and QNetworkProtocol.
void QUrlOperator::dataTransferProgress ( int bytesDone, int bytesTotal,
QNetworkOperation * op ) [signal]
This signal is emitted during data transfer (using put() or get()).
bytesDone specifies how many bytes of bytesTotal have been transferred.
More information about the operation is stored in op, a pointer to the
network operation that is processed. bytesTotal may be -1, which means
that the total number of bytes is not known.
See also QNetworkOperation and QNetworkProtocol.
void QUrlOperator::deleteNetworkProtocol () [protected]
Deletes the currently used network protocol.
void QUrlOperator::finished ( QNetworkOperation * op ) [signal]
This signal is emitted when an operation of some sort finishes, whether
with success or failure. op is a pointer to the operation object, which
contains all the information, including the state, of the operation
which has been finished. Check the state and error code of the
operation object to see whether or not the operation was successful.
See also QNetworkOperation and QNetworkProtocol.
const QNetworkOperation * QUrlOperator::get ( const QString & location =
QString::null ) [virtual]
Tells the network protocol to get data from location or, if this is
QString::null, to get data from the location to which this URL points
(see QUrl::fileName() and QUrl::encodedPathAndQuery()). What happens
then depends on the network protocol. The data() signal is emitted when
data comes in. Because it's unlikely that all data will come in at
once, it is common for multiple data() signals to be emitted. The
dataTransferProgress() signal is emitted while processing the
operation. At the end, finished() (with success or failure) is emitted,
so check the state of the network operation object to see whether or
not the operation was successful.
If location is QString::null, the path of this QUrlOperator should
point to a file when you use this operation. If location is not empty,
it can be a relative URL (a child of the path to which the QUrlOperator
points) or an absolute URL.
For example, to get a web page you might do something like this:
QUrlOperator op( "http://www.whatever.org/cgi-bin/search.pl?cmd=Hello" );
op.get();
For most other operations, the path of the QUrlOperator must point to a
directory. If you want to download a file you could do the following:
QUrlOperator op( "ftp://ftp.whatever.org/pub" );
// do some other stuff like op.listChildren() or op.mkdir( "new_dir" )
op.get( "a_file.txt" );
This will get the data of ftp://ftp.whatever.org/pub/a_file.txt.
Never do anything like this:
QUrlOperator op( "http://www.whatever.org/cgi-bin" );
op.get( "search.pl?cmd=Hello" ); // WRONG!
If location is not empty and relative it must not contain any queries
or references, just the name of a child. So if you need to specify a
query or reference, do it as shown in the first example or specify the
full URL (such as http://www.whatever.org/cgi-bin/search.pl?cmd=Hello)
as location.
See also copy().
void QUrlOperator::getNetworkProtocol () [protected]
Finds a network protocol for the URL and deletes the old network
protocol.
QUrlInfo QUrlOperator::info ( const QString & entry ) const [virtual]
Returns the URL information for the child entry, or returns an empty
QUrlInfo object if there is no information available about entry.
Information about entry is only available after a successfully finished
listChildren() operation.
bool QUrlOperator::isDir ( bool * ok = 0 ) [virtual]
Returns TRUE if the URL is a directory; otherwise returns FALSE. This
may not always work correctly, if the protocol of the URL is something
other than file (local filesystem). If you pass a bool pointer as the
ok argument, *ok is set to TRUE if the result of this function is known
to be correct, and to FALSE otherwise.
void QUrlOperator::itemChanged ( QNetworkOperation * op ) [signal]
This signal is emitted whenever a file which is a child of the URL has
been changed, for example by successfully calling rename(). op is a
pointer to the operation object which contains all the information
about the operation, including the state. op->arg(0) holds the original
file name and op->arg(1) holds the new file name (if it was changed).
See also QNetworkOperation and QNetworkProtocol.
const QNetworkOperation * QUrlOperator::listChildren () [virtual]
Starts listing the children of this URL (e.g. the files in the
directory). The start() signal is emitted before the first entry is
listed and finished() is emitted after the last one. The newChildren()
signal is emitted for each list of new entries. If an error occurs, the
signal finished() is emitted, so be sure to check the state of the
network operation pointer.
Because the operation may not be executed immediately, a pointer to the
QNetworkOperation object created by this function is returned. This
object contains all the data about the operation and is used to refer
to this operation later (e.g. in the signals that are emitted by the
QUrlOperator). The return value can also be 0 if the operation object
couldn't be created.
The path of this QUrlOperator must to point to a directory (because the
children of this directory will be listed), not to a file.
const QNetworkOperation * QUrlOperator::mkdir ( const QString & dirname )
[virtual]
Tries to create a directory (child) with the name dirname. If it is
successful, a newChildren() signal with the new child is emitted, and
the createdDirectory() signal with the information about the new child
is also emitted. The finished() signal (with success or failure) is
emitted after the operation has been processed, so check the state of
the network operation object to see whether or not the operation was
successful.
Because the operation will not be executed immediately, a pointer to
the QNetworkOperation object created by this function is returned. This
object contains all the data about the operation and is used to refer
to this operation later (e.g. in the signals that are emitted by the
QUrlOperator). The return value can also be 0 if the operation object
couldn't be created.
The path of this QUrlOperator must to point to a directory (not a file)
because the new directory will be created in this path.
QString QUrlOperator::nameFilter () const
Returns the name filter of the URL.
See also QUrlOperator::setNameFilter() and QDir::nameFilter().
void QUrlOperator::newChildren ( const QValueList<QUrlInfo> & i,
QNetworkOperation * op ) [signal]
This signal is emitted after listChildren() was called and new children
(i.e. files) have been read from a list of files. i holds the
information about the new files. op is a pointer to the operation
object which contains all the information about the operation,
including the state.
See also QNetworkOperation and QNetworkProtocol.
const QNetworkOperation * QUrlOperator::put ( const QByteArray & data, const
QString & location = QString::null ) [virtual]
This function tells the network protocol to put data in location. If
location is empty (QString::null), it puts the data in the location to
which the URL points. What happens depends on the network protocol.
Depending on the network protocol, some data might come back after
putting data, in which case the data() signal is emitted. The
dataTransferProgress() signal is emitted during processing of the
operation. At the end, finished() (with success or failure) is emitted,
so check the state of the network operation object to see whether or
not the operation was successful.
If location is QString::null, the path of this QUrlOperator should
point to a file when you use this operation. If location is not empty,
it can be a relative (a child of the path to which the QUrlOperator
points) or an absolute URL.
For putting some data to a file you can do the following:
QUrlOperator op( "ftp://ftp.whatever.com/home/me/filename.dat" );
op.put( data );
For most other operations, the path of the QUrlOperator must point to a
directory. If you want to upload data to a file you could do the
following:
QUrlOperator op( "ftp://ftp.whatever.com/home/me" );
// do some other stuff like op.listChildren() or op.mkdir( "new_dir" )
op.put( data, "filename.dat" );
This will upload the data to
ftp://ftp.whatever.com/home/me/filename.dat.
See also copy().
const QNetworkOperation * QUrlOperator::remove ( const QString & filename )
[virtual]
Tries to remove the file (child) filename. If it succeeds the removed()
signal is emitted. finished() (with success or failure) is also emitted
after the operation has been processed, so check the state of the
network operation object to see whether or not the operation was
successful.
Because the operation will not be executed immediately, a pointer to
the QNetworkOperation object created by this function is returned. This
object contains all the data about the operation and is used to refer
to this operation later (e.g. in the signals that are emitted by the
QUrlOperator). The return value can also be 0 if the operation object
couldn't be created.
The path of this QUrlOperator must point to a directory; because if
filename is relative, it will try to remove it in this directory.
void QUrlOperator::removed ( QNetworkOperation * op ) [signal]
This signal is emitted when remove() has been succesful and the file
has been removed.
op is a pointer to the operation object which contains all the
information about the operation, including the state. op->arg(0) holds
the name of the file that was removed.
See also QNetworkOperation and QNetworkProtocol.
const QNetworkOperation * QUrlOperator::rename ( const QString & oldname,
const QString & newname ) [virtual]
Tries to rename the file (child) called oldname to newname. If it
succeeds, the itemChanged() signal is emitted. finished() (with success
or failure) is also emitted after the operation has been processed, so
check the state of the network operation object to see whether or not
the operation was successful.
Because the operation may not be executed immediately, a pointer to the
QNetworkOperation object created by this function is returned. This
object contains all the data about the operation and is used to refer
to this operation later (e.g. in the signals that are emitted by the
QUrlOperator). The return value can also be 0 if the operation object
couldn't be created.
This path of this QUrlOperator must to point to a directory because
oldname and newname are handled relative to this directory.
void QUrlOperator::setNameFilter ( const QString & nameFilter ) [virtual]
Sets the name filter of the URL to nameFilter.
See also QDir::setNameFilter().
void QUrlOperator::start ( QNetworkOperation * op ) [signal]
Some operations (such as listChildren()) emit this signal when they
start processing the operation. op is a pointer to the operation object
which contains all the information about the operation, including the
state.
See also QNetworkOperation and QNetworkProtocol.
void QUrlOperator::startedNextCopy ( const QPtrList<QNetworkOperation> & lst )
[signal]
This signal is emitted if copy() starts a new copy operation. lst
contains all QNetworkOperations related to this copy operation.
See also copy().
void QUrlOperator::stop () [virtual]
Stops the current network operation and removes all this QUrlOperator's
waiting network operations.
RELATED FUNCTION DOCUMENTATIONvoid qInitNetworkProtocols ()
This function registers the network protocols for FTP and HTTP. You
must call this function before you use QUrlOperator for these
protocols.
This function is declared in qnetwork.h.
SEE ALSO
http://doc.trolltech.com/qurloperator.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the
license file included in the distribution for a complete license
statement.
AUTHOR
Generated automatically from the source code.
BUGS
If you find a bug in Qt, please report it as described in
http://doc.trolltech.com/bughowto.html. Good bug reports help us to
help you. Thank you.
The definitive Qt documentation is provided in HTML format; it is
located at $QTDIR/doc/html and can be read using Qt Assistant or with a
web browser. This man page is provided as a convenience for those users
who prefer man pages, although this format is not officially supported
by Trolltech.
If you find errors in this manual page, please report them to qt-
bugs@trolltech.com. Please include the name of the manual page
(qurloperator.3qt) and the Qt version (3.3.8).
Trolltech AS 2 February 2007 QUrlOperator(3qt)