NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:labelText];NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];[paragraphStyle setLineSpacing:LINESPACE];//调整行间距
        [attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [labelText length])];label.attributedText = attributedString;

#define UILABEL_LINE_SPACE 6
#define HEIGHT [ [ UIScreen mainScreen ] bounds ].size.height
//给UILabel设置行间距和字间距
-(void)setLabelSpace:(UILabel*)label withValue:(NSString*)str withFont:(UIFont*)font {NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];paraStyle.lineBreakMode = NSLineBreakByCharWrapping;paraStyle.alignment = NSTextAlignmentLeft;paraStyle.lineSpacing = UILABEL_LINE_SPACE; //设置行间距paraStyle.hyphenationFactor = 1.0;paraStyle.firstLineHeadIndent = 0.0;paraStyle.paragraphSpacingBefore = 0.0;paraStyle.headIndent = 0;paraStyle.tailIndent = 0;//设置字间距 NSKernAttributeName:@1.5fNSDictionary *dic = @{NSFontAttributeName:font, NSParagraphStyleAttributeName:paraStyle, NSKernAttributeName:@1.5f
};NSAttributedString *attributeStr = [[NSAttributedString alloc] initWithString:str attributes:dic];label.attributedText = attributeStr;
}//计算UILabel的高度(带有行间距的情况)
-(CGFloat)getSpaceLabelHeight:(NSString*)str withFont:(UIFont*)font withWidth:(CGFloat)width {NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];paraStyle.lineBreakMode = NSLineBreakByCharWrapping;paraStyle.alignment = NSTextAlignmentLeft;paraStyle.lineSpacing = UILABEL_LINE_SPACE;paraStyle.hyphenationFactor = 1.0;paraStyle.firstLineHeadIndent = 0.0;paraStyle.paragraphSpacingBefore = 0.0;paraStyle.headIndent = 0;paraStyle.tailIndent = 0;NSDictionary *dic = @{NSFontAttributeName:font, NSParagraphStyleAttributeName:paraStyle, NSKernAttributeName:@1.5f
};CGSize size = [str boundingRectWithSize:CGSizeMake(width, HEIGHT) options:NSStringDrawingUsesLineFragmentOrigin attributes:dic context:nil].size;return size.height;
}

NSString  *text = @"This\nis\nsome\nmulti-line\nsample\ntext."
UIFont    *uiFont = [UIFont fontWithName:@"Helvetica" size:17.0];
CTFontRef ctFont = CTFontCreateWithName((CFStringRef) uiFont.fontName, uiFont.pointSize, NULL);//  When you create an attributed string the default paragraph style has a leading
//  of 0.0. Create a paragraph style that will set the line adjustment equal to
//  the leading value of the font.
CGFloat leading = uiFont.lineHeight - uiFont.ascender + uiFont.descender;
CTParagraphStyleSetting paragraphSettings[1] = { kCTParagraphStyleSpecifierLineSpacingAdjustment, sizeof (CGFloat), &leading };CTParagraphStyleRef  paragraphStyle = CTParagraphStyleCreate(paragraphSettings, 1);
CFRange textRange = CFRangeMake(0, text.length);//  Create an empty mutable string big enough to hold our test
CFMutableAttributedStringRef string = CFAttributedStringCreateMutable(kCFAllocatorDefault, text.length);//  Inject our text into it
CFAttributedStringReplaceString(string, CFRangeMake(0, 0), (CFStringRef) text);//  Apply our font and line spacing attributes over the span
CFAttributedStringSetAttribute(string, textRange, kCTFontAttributeName, ctFont);
CFAttributedStringSetAttribute(string, textRange, kCTParagraphStyleAttributeName, paragraphStyle);CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString(string);
CFRange fitRange;CGSize frameSize = CTFramesetterSuggestFrameSizeWithConstraints(framesetter, textRange, NULL, bounds, &fitRange);CFRelease(framesetter);
CFRelease(string);

- (CGFloat)boundingRectWithSize:(CGFloat)widthwithAttributedString:(NSMutableAttributedString *)attrt {CGFloat height = 0;NSStringDrawingOptions options =NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading;CGRect rect = [attrt boundingRectWithSize:CGSizeMake(width, CGFLOAT_MAX)options:optionscontext:nil];height = ceilf(rect.size.height);return height;
}- (CGFloat)stringWidthWithSize:(CGSize)size font:(UIFont *)font {CGFloat width;if ([PAUntils isAtLeastIOS_7_0]) {CGRect rect =[self boundingRectWithSize:sizeoptions:NSStringDrawingUsesLineFragmentOriginattributes:@{NSFontAttributeName : font}context:nil];width = rect.size.width;} else {CGSize strSize = [self sizeWithFont:font constrainedToSize:size];width = strSize.width;}return width;
}