1, demo 1, QStringstr equals FF, bool, ok.

2.inthex is equal to str point to int &；; Ok, 16, double slash hexadecimal double equals 255, and good double equals true.

3.intdec equals str pointing to int &；; Ok, ok double equals false.

4.intline 1 equals line point to int &；; Ok, double equals converts the string 123 into an integer 123.