/** substringFromIndex: --从第from位数 开始截取字符串 */ NSString *str = @"asdfghjkzxcbnm"; NSString *subFromStr = [str substringFromIndex:4]; NSLog(@"-----subFromeStr=%@-----", subFromStr); //ghjkzxcbnm /** substringToIndex: -- 字符串截取到第to位 */ NSString *subToStr = [str substringToIndex:6]; NSLog(@"-----subToStr=%@-----", subToStr); //asdfgh /** substringWithRange: -- 截取range的范围的字符串 */ NSString *subRangeStr = [str substringWithRange:NSMakeRange(3, 4)]; NSLog(@"-----subRangeStr=%@-----", subRangeStr); //fghj /** - (NSComparisonResult)compare:(NSString *)string; - (NSComparisonResult)compare:(NSString *)string options:(NSStringCompareOptions)mask; - (NSComparisonResult)compare:(NSString *)string options:(NSStringCompareOptions)mask range:(NSRange)rangeOfReceiverToCompare; -- 字符串的比较大小 */ NSString *compareStr = @"fgrt"; NSLog(@"-----compare=%ld-----",[str compare:compareStr]);//-1 /** caseInsensitiveCompare -- 比较字母,忽略大小写 */ NSString *caseInsStr = @"adE"; NSLog(@"-----compare=%ld-----", [str compare:caseInsStr]);//1 /** localizedCompare -- 按照 汉字 拼音字母排序 */ NSString *name1 = @"安"; NSLog(@"-----compare=%ld-----",[name1 localizedCompare:@"微微"]); //-1 /** localizedStandardCompare: -- added in 10.6,比较字符串不管是汉子还是字符串 */ NSLog(@"-----comare111==%ld-----", [str localizedStandardCompare:name1]); // 1 /** isEqualToString -- 比较两个字符串是否相等 */ /** hasPrefix: -- 是否包含了前缀 str */ NSLog(@"-----hasPrefix=%d-----", [str hasPrefix:@"as"]); /** hasSuffix: -- 结束字符串中是否包含 str 字符串 */ NSLog(@"-----hasSuffix=%d-----", [str hasSuffix:@"bnm"]); /** commonPrefixWithString: options: -- 找与之开头相同的字符,返回相同开头的字符串 */ NSString *commonPrdfixStr = [str commonPrefixWithString:@"as" options:NSCaseInsensitiveSearch]; NSLog(@"-----commonPrdfixStr=%@-----", commonPrdfixStr); /** containsString: -- 是否包含了某字符串 区分大小写 */ NSLog(@"-----containsString=%d-----", [str containsString:@"Fg"]); //0 /** localizedCaseInsensitiveContainsString: -- 是否包含了某字符串 不区分大小写 */ NSLog(@"-----localizedCaseInsensitiveContainsString=%ld-----", [str localizedStandardCompare:@"Fg"]);