NSString - API
substringWithRange:NSRange
substringFromIndex:NSInteger
substringToIndex:NSInteger
containsString:NSString
hasSuffix:NSString是否有后缀
hasPrefix:NSString是否有前缀
(NSRange) rangeOfString:NSString 子字符串在字符串中的位置
(NSString) stringByAppendingString:NSString
(NSString) stringByAppendingPathComponent:NSString
(NSString)stringByAppendingFormat:@"%@,%@",str1,str2...
(NSString) lowercaseString转成小写
(NSString) uppercaseString以大写字母开头
(NSString) capitalizedString转成大写
(NSData) dataUsingEncoding: NSUTF8StringEncoding NSSTring->NSData
(NSString)stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]剪掉头尾指定字符
(NSArray)componentsSeparatedByString:NSString以某字符串分割字符串
(NSString)stringByReplacingOccurrencesOfString:NSString withString:NSString替换指定字符串
writeToFile: NSString atomically:YES encoding:NSUTF8StringEncoding
stringWithContentsOfFile:NSString(FilePath)encoding:NSUTF8StringEncoding error: error
从文件中读取字符串
caseInsensitiveCompare:NSString不区分大小写比较