一 compare
1 应该用isEqualToString
2 compare
这个可以提供排列。而且还可以进行按照字符串的字符长度进行排列。
NSString *str= [NSString stringWithFormat:@"100"]; NSString *str2 =[NSString stringWithFormat:@"100"]; NSComparisonResult resul = [str compare:str2 options:NSCaseInsensitiveSearch|NSNumericSearch]; if (resul == NSOrderedSame) { NSLog(@"They are same!"); }
二 contain
hasPrefix
hasSuffix
rangeOfString
eg:
NSRange range = [str rangeOfString:@"2"]; NSLog(@"location:%i length:%i",range.location, range.length);
third: NSMutableString
NSMutableString *multabstr =[NSMutableString stringWithCapacity:[str length]]; [multabstr appendString:str]; NSLog(@"%@",multabstr);