转载来源 NSCharacterSet其实是许多字符或者数字或者符号的组合，在网络处理的时候会用到
NSMutableCharacterSet *base = [NSMutableCharacterSet lowercaseLetterCharacterSet]; //字母
NSCharacterSet *decimalDigit = [NSCharacterSet decimalDigitCharacterSet]; //十进制数字
[base formUnionWithCharacterSet:decimalDigit]; //字母加十进制
NSString *string = @"ax@d5s#@sfn$5`SF$$%x^(#e{]e";
//用上面的base隔开string然后组成一个数组，然后通过componentsJoinedByString，来连接成一个字符串
NSLog(@"%@",[[string componentsSeparatedByCharactersInSet:base] componentsJoinedByString:@"-"]);
[base invert]; //非 字母加十进制
NSLog(@"%@",[[string componentsSeparatedByCharactersInSet:base] componentsJoinedByString:@"-"]);
答应结果：
ax@d-s#@sfn−‘SF$%x^(#e{]e
判断字符串是否是纯数字
- (BOOL)isPureNumandCharacters:(NSString *)string
{
string = [string stringByTrimmingCharactersInSet:[NSCharacterSet decimalDigitCharacterSet]];
if(string.length > 0)
{
return NO;
}
return YES;
}
