label调整字间距，调整行间距

number = 1.0f

//调整字间距
    CFNumberRef num = CFNumberCreate(kCFAllocatorDefault,kCFNumberSInt 8 Type,&number;);
    [attributedString addAttribute :( id )kCTKernAttributeName value :(__bridge id )num range :NSMakeRange( 0 , [attributedString length ])];
    //调整行间距
    [attributedString addAttribute : NSParagraphStyleAttributeName value :paragraphStyle range :NSMakeRange( 0 , [_messageLabel .text length ])];

    _messageLabel.attributedText = attributedString;