qBound
template <typename T>const T &qBound(const T &min, const T &val, const T &max)
Returns val bounded by min and max. This is equivalent to qMax(min, qMin(val, max)). 先比较val 和 max选出最小的值,然后以这个最小的值和min相比,选出最大的值。
int myValue = 10;
int minValue = 2;
int maxValue = 6;
int boundedValue = qBound(minValue, myValue, maxValue);
// boundedValue == 6