（一）编码转换
QString:
---------------------------------------------------------------------------------
普通成员函数：
QByteArray toAscii () const
QByteArray toLatin1 () const
QByteArray toLocal8Bit () const
QByteArray toUtf8 () const
const ushort * utf16 () const
const QChar * unicode () const
QVector<uint> toUcs4 () const
std::string toStdString () const
std::wstring toStdWString () const
int toWCharArray ( wchar_t * array ) const
静态成员函数：
QString fromAscii ( const char * str, int size = -1 )
QString fromLatin1 ( const char * str, int size = -1 )
QString fromLocal8Bit ( const char * str, int size = -1 )
QString fromUtf8 ( const char * str, int size = -1 )
QString fromUtf16 ( const ushort * unicode, int size = -1 )
QString fromRawData ( const QChar * unicode, int size )
QString fromUcs4 ( const uint * unicode, int size = -1 )
QString fromStdString ( const std::string & str )
QString fromStdWString ( const std::wstring & str )
QString fromWCharArray ( const wchar_t * string, int size = -1 )
QByteArray：
---------------------------------------------------------------------------------
普通成员函数：
const char * constData () const
char * data ()
const char * data () const
QByteArray toBase64 () const
QByteArray toHex () const
QByteArray toPercentEncoding ( const QByteArray & exclude = QByteArray(), const QByteArray & include = QByteArray(), char percent = '%' ) const
QByteArray & setRawData ( const char * data, uint size )
静态成员函数：
QByteArray fromBase64 ( const QByteArray & base64 )
QByteArray fromHex ( const QByteArray & hexEncoded )
QByteArray fromPercentEncoding ( const QByteArray & input, char percent = '%' )
QByteArray fromRawData ( const char * data, int size )
（二）类型转换
QString:
---------------------------------------------------------------------------------
普通成员函数：
int toInt ( bool * ok = 0, int base = 10 ) const
uint toUInt ( bool * ok = 0, int base = 10 ) const
short toShort ( bool * ok = 0, int base = 10 ) const
ushort toUShort ( bool * ok = 0, int base = 10 ) const
long toLong ( bool * ok = 0, int base = 10 ) const
ulong toULong ( bool * ok = 0, int base = 10 ) const
qlonglong toLongLong ( bool * ok = 0, int base = 10 ) const
qulonglong toULongLong ( bool * ok = 0, int base = 10 ) const
double toDouble ( bool * ok = 0 ) const
float toFloat ( bool * ok = 0 ) const
QString & setNum ( int n, int base = 10 )
QString & setNum ( uint n, int base = 10 )
QString & setNum ( short n, int base = 10 )
QString & setNum ( ushort n, int base = 10 )
QString & setNum ( long n, int base = 10 )
QString & setNum ( ulong n, int base = 10 )
QString & setNum ( qlonglong n, int base = 10 )
QString & setNum ( qulonglong n, int base = 10 )
QString & setNum ( double n, char format = 'g', int precision = 6 )
QString & setNum ( float n, char format = 'g', int precision = 6 )
静态成员函数：
QString number ( int n, int base = 10 )
QString number ( uint n, int base = 10 )
QString number ( long n, int base = 10 )
QString number ( ulong n, int base = 10 )
QString number ( qlonglong n, int base = 10 )
QString number ( qulonglong n, int base = 10 )
QString number ( double n, char format = 'g', int precision = 6 )
QByteArray：
---------------------------------------------------------------------------------
普通成员函数：
int toInt ( bool * ok = 0, int base = 10 ) const
uint toUInt ( bool * ok = 0, int base = 10 ) const
short toShort ( bool * ok = 0, int base = 10 ) const
ushort toUShort ( bool * ok = 0, int base = 10 ) const
long toLong ( bool * ok = 0, int base = 10 ) const
ulong toULong ( bool * ok = 0, int base = 10 ) const
qlonglong toLongLong ( bool * ok = 0, int base = 10 ) const
qulonglong toULongLong ( bool * ok = 0, int base = 10 ) const
double toDouble ( bool * ok = 0 ) const
float toFloat ( bool * ok = 0 ) const
QByteArray & setNum ( int n, int base = 10 )
QByteArray & setNum ( uint n, int base = 10 )
QByteArray & setNum ( short n, int base = 10 )
QByteArray & setNum ( ushort n, int base = 10 )
QByteArray & setNum ( qlonglong n, int base = 10 )
QByteArray & setNum ( qulonglong n, int base = 10 )
QByteArray & setNum ( double n, char f = 'g', int prec = 6 )
QByteArray & setNum ( float n, char f = 'g', int prec = 6 )
静态成员函数：
QByteArray number ( int n, int base = 10 )
QByteArray number ( uint n, int base = 10 )
QByteArray number ( qlonglong n, int base = 10 )
QByteArray number ( qulonglong n, int base = 10 )
QByteArray number ( double n, char f = 'g', int prec = 6 )