內容

• 公共函數
• 靜態公共成員
• 詳細描述

QMetaEnum 類

The QMetaEnum 類提供枚舉器的有關元數據。 更多...

頭：	#include <QMetaEnum>
qmake:	QT += core

• 所有成員列錶，包括繼承成員

公共函數

bool	isFlag () const
bool	isScoped () const
bool	isValid () const
const char *	key (int index ) const
int	keyCount () const
int	keyToValue (const char * key , bool * ok = Q_NULLPTR) const
int	keysToValue (const char * keys , bool * ok = Q_NULLPTR) const
const char *	name () const
const char *	scope () const
int	value (int index ) const
const char *	valueToKey (int value ) const
QByteArray	valueToKeys (int value ) const

靜態公共成員

QMetaEnum

fromType ()

詳細描述

The QMetaEnum 類提供枚舉器的有關元數據。

使用 name () for the enumerator's name. The enumerator's keys (names of each enumerated item) are returned by key ()；使用 keyCount () 能查找按鍵數。 isFlag () returns whether the enumerator is meant to be used as a flag, meaning that its values can be combined using the OR operator.

The conversion functions keyToValue (), valueToKey (), keysToValue ()，和 valueToKeys () allow conversion between the integer representation of an enumeration or set value and its literal representation. The scope () function returns the class scope this enumerator was declared in.

另請參閱 QMetaObject , QMetaMethod ，和 QMetaProperty .

成員函數文檔編製

[static] QMetaEnum QMetaEnum:: fromType ()

返迴 QMetaEnum corresponding to the type in the template parameter. The enum needs to be declared with Q_ENUM .

該函數在 Qt 5.5 引入。

bool QMetaEnum:: isFlag () const

返迴 true 若此枚舉器被用作標誌；否則返迴 false。

When used as flags, enumerators can be combined using the OR operator.

另請參閱 keysToValue () 和 valueToKeys ().

bool QMetaEnum:: isScoped () const

返迴 true if this enumerator is declared as a C++11 enum class; otherwise returns false.

該函數在 Qt 5.8 引入。

bool QMetaEnum:: isValid () const

返迴 true if this enum is valid (has a name); otherwise returns false.

另請參閱 name ().

const char *QMetaEnum:: key ( int index ) const

Returns the key with the given index , or 0 if no such key exists.

另請參閱 keyCount (), value ()，和 valueToKey ().

int QMetaEnum:: keyCount () const

返迴按鍵數。

另請參閱 key ().

int QMetaEnum:: keyToValue (const char * key , bool * ok = Q_NULLPTR) const

Returns the integer value of the given enumeration key ，或 -1 若 key 未定義。

若 key is not defined, * ok is set to false; otherwise * ok 被設為 true。

對於標誌類型，使用 keysToValue ().

另請參閱 valueToKey (), isFlag ()，和 keysToValue ().

int QMetaEnum:: keysToValue (const char * keys , bool * ok = Q_NULLPTR) const

Returns the value derived from combining together the values of the keys using the OR operator, or -1 if keys is not defined. Note that the strings in keys must be '|'-separated.

若 keys is not defined, * ok is set to false; otherwise * ok 被設為 true。

另請參閱 isFlag (), valueToKey ()，和 valueToKeys ().

const char *QMetaEnum:: name () const

Returns the name of the enumerator (without the scope).

例如， Qt::AlignmentFlag 枚舉擁有 AlignmentFlag as the name and Qt as the scope.

另請參閱 isValid () 和 scope ().

const char *QMetaEnum:: scope () const

Returns the scope this enumerator was declared in.

例如， Qt::AlignmentFlag 枚舉擁有 Qt as the scope and AlignmentFlag as the name.

另請參閱 name ().

int QMetaEnum:: value ( int index ) const

Returns the value with the given index ; or returns -1 if there is no such value.

另請參閱 keyCount (), key ()，和 keyToValue ().

const char *QMetaEnum:: valueToKey ( int value ) const

Returns the string that is used as the name of the given enumeration value , or 0 if value 未定義。

對於標誌類型，使用 valueToKeys ().

另請參閱 isFlag () 和 valueToKeys ().

QByteArray QMetaEnum:: valueToKeys ( int value ) const

Returns a byte array of '|'-separated keys that represents the given value .

另請參閱 isFlag (), valueToKey ()，和 keysToValue ().