属性字段
UIFont *font = [UIFont systemFontOfSize:30];
//段落设置
NSMutableParagraphStyle *paragraph = [[NSMutableParagraphStyle alloc] init];
paragraph.lineSpacing = 10.0;//行间距
paragraph.paragraphSpacing = 20.0;//段落间距
paragraph.alignment = NSTextAlignmentJustified;//自动换行
paragraph.firstLineHeadIndent = 30.0;//首行缩进
// paragraph.headIndent = 50;//行首缩进，不包括首行
paragraph.tailIndent = -10;//行尾缩进，正数从左边计算距离，负数从右边算起
/*
NSLineBreakByWordWrapping = 0, //自动换行，单词切断
NSLineBreakByCharWrapping, //自动换行，字母切断
NSLineBreakByClipping, //非自动换行，不切断
NSLineBreakByTruncatingHead, //省略方式 ...abc
NSLineBreakByTruncatingTail, //省略方式 aa...bc
NSLineBreakByTruncatingMiddle //省略方式 abc...
*/
paragraph.lineBreakMode = NSLineBreakByCharWrapping;//断行方式
// paragraph.baseWritingDirection = NSWritingDirectionRightToLeft;//句子方向
paragraph.paragraphSpacingBefore = 55;//段前距
paragraph.hyphenationFactor = 1;//连字符属性，取值 0 到 1 之间，开启断词功能
//阴影
NSShadow *shadow = [[NSShadow alloc] init];
shadow.shadowColor = [UIColor grayColor];
shadow.shadowOffset = CGSizeMake(2, 1);
NSDictionary *dic = @{NSFontAttributeName:font,//字体
NSParagraphStyleAttributeName:paragraph,//段落，NSParagraphStyle对象
NSForegroundColorAttributeName:[UIColor orangeColor],//字体颜色
// NSBackgroundColorAttributeName:[UIColor grayColor],//字体背景色
NSLigatureAttributeName:@(1),//连字符
NSKernAttributeName:@(5),//字间距
NSStrikethroughStyleAttributeName:@(1),//删除线0或1，NSNumber类型
NSUnderlineStyleAttributeName:@(1),//下划线
// NSStrokeColorAttributeName:[UIColor greenColor],//边线颜色
// NSStrokeWidthAttributeName:@(1),//边线宽度
NSShadowAttributeName:shadow,//阴影,NSShadow对象
NSVerticalGlyphFormAttributeName:@(0)//横竖排版，iOS对0以外的未定义。
};
参考文章
iOS富文本
iOS 字符属性NSAttributedString描述
