QString number ( long n, int base = 10 )
QString number ( double n, char format = 'g', int precision = 6 )
QString number ( ulong n, int base = 10 )
QString number ( int n, int base = 10 )
QString number ( uint n, int base = 10 )
QString number ( qlonglong n, int base = 10 )
QString number ( qulonglong n, int base = 10 )
用double试一下?