Qt常用类

qt常用类判断:boolisDigit()const;//判断是否是十进制数字('0'-'9')boolisLetter()const;//判断是否是字??boolisLetterOrNumber()const;//判断力是否是字母或数??boolisLower()const;判断是否是小写字??boolisUpper()const;//判断是否是大写字??boolisNull()const;//判断是否是空字符'0'boolisPrint()const;//判断是否是可打印字符boolisSpace()const;//判断是否是分隔符,包括空格??转换:chartoAscii()const;//得到字符的ASCII??QChartoLower()const;//转换成小写字??QChartoUpper()const;转换成大写字??ushortunicode()const;//得到Unicode编码比较:booloperator!=(QCharc1,QCharc2);//判断c1是否不等于c2booloperator<(QCharc1,QCharc2);//  ......是否小于...booloperator<=(QCharc1,QCharc2);booloperator==(QCharc1,QCharc2);booloperator>(QCharc1,QCharc2);booloperator>=(QCharc1,QCharc2);判断:           boolisEmpty()const;//判断是否为空字符??转换:           将字符串转换成数??double