iOS 字符串大小写转换(系统方法)

1、所有的小写字母转换成大写

　　NSString *ceshi=@"You do not have the corresponding permissions, please contact the system administrator to add";

    //所有的小写字母都转换成大写

    NSLog(@"first:%@",[ceshi uppercaseString]);

　　first:YOU DO NOT HAVE THE CORRESPONDING PERMISSIONS, PLEASE CONTACT THE SYSTEM ADMINISTRATOR TO ADD

2、所有的大写字母转换成小写

    NSLog(@"second:%@",[ceshi lowercaseString]);

　　second:you do not have the corresponding permissions, please contact the system administrator to add

3、所有的首字母大写，其余变成小写

    NSLog(@"third:%@",[ceshi capitalizedString]);

　　third:You Do Not Have The Corresponding Permissions, Please Contact The System Administrator To Add