QRegExpValidator Class Reference

The QRegExpValidator class is used to check a string against a regular expression. More...

#include <qvalidator.h>

Inheritance diagram for QRegExpValidator:

Public Functions
	QRegExpValidator (QObject *parent=0)
	Constructs a validator with a parent object that accepts any string (including an empty one) as valid. More...
	QRegExpValidator (const QRegExp &rx, QObject *parent=0)
	Constructs a validator with a parent object that accepts all strings that match the regular expression rx. More...
const QRegExp &	regExp () const
void	setRegExp (const QRegExp &rx)
virtual QValidator::State	validate (QString &input, int &pos) const
	Returns Acceptable if input is matched by the regular expression for this validator, Intermediate if it has matched partially (i.e. More...
	~QRegExpValidator ()
	Destroys the validator. More...
Public Functions inherited from QValidator
virtual void	fixup (QString &) const
	This function attempts to change input to be valid according to this validator's rules. More...
QLocale	locale () const
	Returns the locale for the validator. More...
	QValidator (QObject *parent=0)
	Sets up the validator. More...
void	setLocale (const QLocale &locale)
	Sets the locale that will be used for the validator. More...
	~QValidator ()
	Destroys the validator, freeing any storage and other resources used. More...
Public Functions inherited from QObject
bool	blockSignals (bool b)
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it). More...
const QObjectList &	children () const
	Returns a list of child objects. More...
bool	connect (const QObject *sender, const char *signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const
bool	disconnect (const char *signal=0, const QObject *receiver=0, const char *member=0)
bool	disconnect (const QObject *receiver, const char *member=0)
void	dumpObjectInfo ()
	Dumps information about signal connections, etc. More...
void	dumpObjectTree ()
	Dumps a tree of children to the debug output. More...
QList< QByteArray >	dynamicPropertyNames () const
	Returns the names of all properties that were dynamically added to the object using setProperty(). More...
virtual bool	event (QEvent *)
	This virtual function receives events to an object and should return true if the event e was recognized and processed. More...
virtual bool	eventFilter (QObject *, QEvent *)
	Filters events if this object has been installed as an event filter for the watched object. More...
template<typename T >
T	findChild (const QString &aName=QString()) const
	Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. More...
template<typename T >
QList< T >	findChildren (const QString &aName=QString()) const
	Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. More...
template<typename T >
QList< T >	findChildren (const QRegExp &re) const
bool	inherits (const char *classname) const
	Returns true if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns false. More...
void	installEventFilter (QObject *)
	Installs an event filter filterObj on this object. More...
bool	isWidgetType () const
	Returns true if the object is a widget; otherwise returns false. More...
void	killTimer (int id)
	Kills the timer with timer identifier, id. More...
virtual const QMetaObject *	metaObject () const
	Returns a pointer to the meta-object of this object. More...
void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children. More...
QString	objectName () const
QObject *	parent () const
	Returns a pointer to the parent object. More...
QVariant	property (const char *name) const
	Returns the value of the object's name property. More...
Q_INVOKABLE	QObject (QObject *parent=0)
	Constructs an object with parent object parent. More...
void	removeEventFilter (QObject *)
	Removes an event filter object obj from this object. More...
void	setObjectName (const QString &name)
void	setParent (QObject *)
	Makes the object a child of parent. More...
bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value. More...
void	setUserData (uint id, QObjectUserData *data)
bool	signalsBlocked () const
	Returns true if signals are blocked; otherwise returns false. More...
int	startTimer (int interval)
	Starts a timer and returns a timer identifier, or returns zero if it could not start a timer. More...
QThread *	thread () const
	Returns the thread in which the object lives. More...
QObjectUserData *	userData (uint id) const
virtual	~QObject ()
	Destroys the object, deleting all its child objects. More...

Properties
QRegExp	r
QRegExp	regExp
	the regular expression used for validation More...

Additional Inherited Members
Public Types inherited from QValidator
enum	State { Invalid, Intermediate, Acceptable }
	This enum type defines the states in which a validated string can exist. More...
Public Slots inherited from QObject
void	deleteLater ()
	Schedules this object for deletion. More...
Signals inherited from QObject
void	destroyed (QObject *=0)
	This signal is emitted immediately before the object obj is destroyed, and can not be blocked. More...
Static Public Functions inherited from QObject
static bool	connect (const QObject *sender, const char *signal, const QObject *receiver, const char *member, Qt::ConnectionType=Qt::AutoConnection)
	Creates a connection of the given type from the signal in the sender object to the method in the receiver object. More...
static bool	connect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)
static bool	disconnect (const QObject *sender, const char *signal, const QObject *receiver, const char *member)
	Disconnects signal in object sender from method in object receiver. More...
static bool	disconnect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &member)
static uint	registerUserData ()
static QString	tr (const char *sourceText, const char *comment=0, int n=-1)
static QString	trUtf8 (const char *sourceText, const char *comment=0, int n=-1)
Static Public Variables inherited from QObject
static const QMetaObject	staticMetaObject
	This variable stores the meta-object for the class. More...
Protected Functions inherited from QValidator
	QValidator (QObjectPrivate &d, QObject *parent)
	QValidator (QValidatorPrivate &d, QObject *parent)
Protected Functions inherited from QObject
virtual void	childEvent (QChildEvent *)
	This event handler can be reimplemented in a subclass to receive child events. More...
virtual void	connectNotify (const char *signal)
	This virtual function is called when something has been connected to signal in this object. More...
virtual void	customEvent (QEvent *)
	This event handler can be reimplemented in a subclass to receive custom events. More...
virtual void	disconnectNotify (const char *signal)
	This virtual function is called when something has been disconnected from signal in this object. More...
	QObject (QObjectPrivate &dd, QObject *parent=0)
int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal. More...
QObject *	sender () const
	Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns 0. More...
int	senderSignalIndex () const
virtual void	timerEvent (QTimerEvent *)
	This event handler can be reimplemented in a subclass to receive timer events for the object. More...
Protected Variables inherited from QObject
QScopedPointer< QObjectData >	d_ptr
Static Protected Variables inherited from QObject
static const QMetaObject	staticQtMetaObject
Related Functions inherited from QObject
T	qFindChildqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QRegExp &regExp)()
T *	qobject_cast (QObject *object)
	QObjectList
void *	qt_find_obj_child (QObject *parent, const char *type, const QString &name)
	Returns a pointer to the object named name that inherits type and with a given parent. More...

Detailed Description

The QRegExpValidator class is used to check a string against a regular expression.

QRegExpValidator uses a regular expression (regexp) to determine whether an input string is Acceptable , Intermediate , or Invalid . The regexp can either be supplied when the QRegExpValidator is constructed, or at a later time.

When QRegExpValidator determines whether a string is Acceptable or not, the regexp is treated as if it begins with the start of string assertion (^) and ends with the end of string assertion ($); the match is against the entire input string, or from the given position if a start position greater than zero is given.

If a string is a prefix of an Acceptable string, it is considered Intermediate . For example, "" and "A" are Intermediate for the regexp [A-Z][0-9] (whereas "_" would be Invalid ).

For a brief introduction to Qt's regexp engine, see QRegExp .

Example of use:

// regexp: optional '-' followed by between 1 and 3 digits
QRegExp rx("-?\\d{1,3}");
QValidator *validator = new QRegExpValidator(rx, this);

QLineEdit *edit = new QLineEdit(this);
edit->setValidator(validator);

Below we present some examples of validators. In practice they would normally be associated with a widget as in the example above.

// integers 1 to 9999
QRegExp rx("[1-9]\\d{0,3}");
// the validator treats the regexp as "^[1-9]\\d{0,3}$"
QRegExpValidator v(rx, 0);
QString s;
int pos = 0;

s = "0";     v.validate(s, pos);    // returns Invalid
s = "12345"; v.validate(s, pos);    // returns Invalid
s = "1";     v.validate(s, pos);    // returns Acceptable

rx.setPattern("\\S+");            // one or more non-whitespace characters
v.setRegExp(rx);
s = "myfile.txt";  v.validate(s, pos); // Returns Acceptable
s = "my file.txt"; v.validate(s, pos); // Returns Invalid

// A, B or C followed by exactly five digits followed by W, X, Y or Z
rx.setPattern("[A-C]\\d{5}[W-Z]");
v.setRegExp(rx);
s = "a12345Z"; v.validate(s, pos);        // Returns Invalid
s = "A12345Z"; v.validate(s, pos);        // Returns Acceptable
s = "B12";     v.validate(s, pos);        // Returns Intermediate

// match most 'readme' files
rx.setPattern("read\\S?me(\.(txt|asc|1st))?");
rx.setCaseSensitive(false);
v.setRegExp(rx);
s = "readme";      v.validate(s, pos); // Returns Acceptable
s = "README.1ST";  v.validate(s, pos); // Returns Acceptable
s = "read me.txt"; v.validate(s, pos); // Returns Invalid
s = "readm";       v.validate(s, pos); // Returns Intermediate

See also

QRegExp, QIntValidator, QDoubleValidator, {Settings Editor Example}

Definition at line 182 of file qvalidator.h.

Constructors and Destructors

QRegExpValidator() [1/2]

QRegExpValidator::QRegExpValidator ( QObject *  parent = 0 )

explicit

Constructs a validator with a parent object that accepts any string (including an empty one) as valid.

Definition at line 879 of file qvalidator.cpp.

Referenced by QRegExpValidator().

    : QValidator(parent), r(QString::fromLatin1(".*"))
{
}

QRegExpValidator() [2/2]

QRegExpValidator::QRegExpValidator	(	const QRegExp &	rx,
		QObject *	parent = 0
	)

Constructs a validator with a parent object that accepts all strings that match the regular expression rx.

The match is made against the entire string; e.g. if the regexp is [A-Fa-f0-9]+ it will be treated as ^[A-Fa-f0-9]+$.

Definition at line 892 of file qvalidator.cpp.

    : QValidator(parent), r(rx)
{
}

~QRegExpValidator()

QRegExpValidator::~QRegExpValidator

(

)

Destroys the validator.

Definition at line 939 of file qvalidator.cpp.

{
}

Functions

regExp()

const QRegExp& QRegExpValidator::regExp ( ) const

inline

Definition at line 195 of file qvalidator.h.

{ return r; } // ### make inline for 5.0

setRegExp()

void QRegExpValidator::setRegExp

(

const QRegExp &

rx

)

Definition at line 983 of file qvalidator.cpp.

{
    r = rx;
}

validate()

QValidator::State QRegExpValidator::validate ( QString &  input, int &  pos  ) const

virtual

Returns Acceptable if input is matched by the regular expression for this validator, Intermediate if it has matched partially (i.e.

could be a valid match if additional valid characters are added), and Invalid if input is not matched.

The pos parameter is set to the length of the input parameter.

For example, if the regular expression is \w\d\d (word-character, digit, digit) then "A57" is Acceptable , "E5" is Intermediate , and "+9" is Invalid .

See also

QRegExp::exactMatch()

Implements QValidator.

Definition at line 958 of file qvalidator.cpp.

{
    if (r.exactMatch(input)) {
        return Acceptable;
    } else {
        if (const_cast<QRegExp &>(r).matchedLength() == input.size()) {
            return Intermediate;
        } else {
            pos = input.size();
            return Invalid;
        }
    }
}

Properties

r

QRegExp QRegExpValidator::r

private

Definition at line 206 of file qvalidator.h.

Referenced by QRegExpValidator(), setRegExp(), and validate().

regExp

QRegExpValidator::regExp

private

the regular expression used for validation

By default, this property contains a regular expression with the pattern .* that matches any string.

Definition at line 185 of file qvalidator.h.

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The documentation for this class was generated from the following files:

• /src/gui/widgets/qvalidator.h
• /src/gui/widgets/qvalidator.cpp