https://blog.csdn.net/GraceLand525/article/details/48625593
Qt::CaseSensitivity cs = Qt::CaseInsensitive; if (!vidstring.isEmpty() && !vidstring.compare(varmap.usb_vid, cs) == 0) ivid = 1; if (!pidstring.isEmpty() && !pidstring.compare(varmap.usb_pid, cs) == 0) ipid = 1;