QString 保留小数点后一位数 & QT int 转16进制QString并补零

http://blog.youkuaiyun.com/gdizcm/article/details/54728381

QString 保留小数点后一位。

double num;

QString::number(num,'f',1));  //保留几位1就改成几

[static] QString QString::number(double n, char format = 'g', int precision = 6)

The argument format can be one of the following:

Format	Meaning
e	format as [-]9.9e[+|-]999
E	format as [-]9.9E[+|-]999
f	format as [-]9.9
g	use e or f format, whichever is the most concise
G	use E or f format, whichever is the most concise

int 转16进制QString并补零

int vibID;

QString key = QString("%1").arg(vibID, 8, 16, QLatin1Char('0'));   //8代表宽度，16表示16进制，空位补零

QString QString::arg(int a, int fieldWidth = 0, int base = 10, QChar fillChar = QLatin1Char( ' ' )) const