正規表現周り

NSRegular.m

    // 文字列置換
    NSString *string =@"hogehogehoge";  // 置換対象文字列
    NSString *template = @"<br/>";   // 置換後文字列
    NSString *replaced = [string stringByReplacingOccurrencesOfString:@"\n" withString:template];

    // 文字列検索　<en-note>の開始位置を調べる
    NSString *pattern = @"<en-note>";
    NSRange rangeFrom = [content rangeOfString:pattern];
    if(rangeFrom.location == NSNotFound){
        return nil;
    }
      
    // 正規表現検索　<en-note>の開始位置を調べる
    NSString *pattern = @"<en-note[^>]*>";
    NSRange rangeFrom = [content rangeOfString:pattern options:NSRegularExpressionSearch];
    if(rangeFrom.location == NSNotFound){
        return nil;
    }

      // 正規表現検索
    NSString *string = @"red. blue. <ss type> yellow. green. blue. </ss> black. white.<ss type> hoge </ss>aaaa";
    NSError *error   = nil;
    NSRegularExpression *regexp = [NSRegularExpression regularExpressionWithPattern:@"<ss type>.+?</ss>" options:0 error:&error];
    if (error != nil) {
        NSLog(@"%@", error);
    } else {
        NSArray *matchs = [regexp matchesInString:string options:0 range:NSMakeRange(0, string.length)];
        for(NSTextCheckingResult *match in matchs){
            int count = (int)match.numberOfRanges;
            for(int i = 0; i < count; i++){
                NSLog(@"%@", [string substringWithRange:[match rangeAtIndex:i]]);
            }            
        }
    }

  // 正規表現置換
    NSError *error   = nil;
    NSRegularExpression *regexp = [NSRegularExpression regularExpressionWithPattern:@"\\n" options:0 error:&error];
    NSString *replaced = [regexp stringByReplacingMatchesInString:string options:0 range:NSMakeRange(0,string.length) withTemplate:template];