由于項目中增加了鏈接和自定義表情等功能，最近一周都在查找富文本這塊的實現，之前的用過的RTLabel和TTTAttributedLabel由于實現不是那么方便高度計算不靈活，讓我這次想到了YY大神的YYText，使用中覺得非常方便好用，于是記下自己的學習過程。

1.匹配超鏈接

// 測試文本
NSString *text = @"這是一個超鏈接http://www.lxweimin.com/users/c75b8e27dc43這是一個超鏈接";

// 轉成可變屬性字符串
    NSMutableAttributedString * mAttributedString = [NSMutableAttributedString new];

// 調整行間距段落間距
NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
    [paragraphStyle setLineSpacing:2]; 
    [paragraphStyle setParagraphSpacing:4]; 

// 設置文本屬性
    NSDictionary *attri = [NSDictionary dictionaryWithObjects:@[font, [UIColor blackColor], paragraphStyle] forKeys:@[NSFontAttributeName, NSForegroundColorAttributeName, NSParagraphStyleAttributeName]];
    [mAttributedString appendAttributedString:[[NSAttributedString alloc] initWithString:self attributes:attri]];

// 匹配條件
NSString *regulaStr = @"((http[s]{0,1}|ftp)://[a-zA-Z0-9\\.\\-]+\\.([a-zA-Z]{2,4})(:\\d+)?(/[a-zA-Z0-9\\.\\-~!@#$%^&*+?:_/=<>]*)?)|(www.[a-zA-Z0-9\\.\\-]+\\.([a-zA-Z]{2,4})(:\\d+)?(/[a-zA-Z0-9\\.\\-~!@#$%^&*+?:_/=<>]*)?)";

NSError *error = NULL;
// 根據匹配條件，創建了一個正則表達式
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:regulaStr
                                                                           options:NSRegularExpressionCaseInsensitive
                                                                             error:&err];
    if (!regex) {
        NSLog(@"正則創建失敗error！= %@", [err localizedDescription]);
    } else {
        NSArray *allMatches = [regex matchesInString:mAttributedString.string options:NSMatchingReportCompletion range:NSMakeRange(0, mAttributedString.string.length)];
        for (NSTextCheckingResult *match in allMatches) {
            NSString *substrinsgForMatch2 = [mAttributedString.string substringWithRange:match.range];
            NSMutableAttributedString *one = [[NSMutableAttributedString alloc] initWithString:substrinsgForMatch2];
            // 利用YYText設置一些文本屬性
            one.yy_font = font;
            one.yy_underlineStyle = NSUnderlineStyleSingle;
            one.yy_color = [UIColor colorWithRed:0.093 green:0.492 blue:1.000 alpha:1.000];
            
            YYTextBorder *border = [YYTextBorder new];
            border.cornerRadius = 3;
            border.insets = UIEdgeInsetsMake(-2, -1, -2, -1);
            border.fillColor = [UIColor colorWithWhite:0.000 alpha:0.220];
            
            YYTextHighlight *highlight = [YYTextHighlight new];
            [highlight setBorder:border];
            [one yy_setTextHighlight:highlight range:one.yy_rangeOfAll];
            // 根據range替換字符串
            [mAttributedString replaceCharactersInRange:match.range withAttributedString:one];
        }
    }

// 使用YYLabel顯示
YYLabel *label = [YYLabel new];
    label.userInteractionEnabled = YES;
    label.numberOfLines = 0;
    label.textVerticalAlignment = YYTextVerticalAlignmentTop;
    label.size = CGSizeMake(260, 260);
    label.center = CGPointMake(self.view.width / 2, 200);
    label.attributedText = mAttributedString;
    [self.view addSubview:label];
    label.highlightTapAction = ^(UIView *containerView, NSAttributedString *text, NSRange range, CGRect rect) {
        NSString *string = [NSString stringWithFormat:@"Tap: %@",[text.string substringWithRange:range]];
        NSLog(@"%@", string);
    };

// 利用YYTextLayout計算高度
YYTextContainer *container = [YYTextContainer containerWithSize:CGSizeMake(260, MAXFLOAT)];
    YYTextLayout *textLayout = [YYTextLayout layoutWithContainer:container text: mAttributedString];
    label.height = textLayout.textBoundingSize.height;

未完待續 > 有時間繼續整理自定義表情這塊的實現...