UILabel根据内容调节高度

UILable_resize

/*根据uilabel的内容决定uilabel的高度--iOS7之前*/
    CGSize maximumSize = CGSizeMake(scrollView.width - 10, 999);
    NSString *dateString = _passport_useZone.text;
    UIFont *dateFont = [UIFont fontWithName:@"Helvetica" size:14];
    CGSize dateStringSize = [dateString sizeWithFont:dateFont constrainedToSize:maximumSize lineBreakMode:_passport_useZone.lineBreakMode];
    CGRect dateFrame = CGRectMake(5, _passport_money.bottom, scrollView.width - 10, dateStringSize.height);
    _passport_useZone.frame = dateFrame;
    
/*iOS7之后*
    CGSize maximumSize = CGSizeMake(300, 9999);
    NSString *dateString = @"The date today is January 1st, 1999";
    UIFont *dateFont = [UIFont fontWithName:@"Helvetica" size:14];
    NSDictionary * tdic = [NSDictionary dictionaryWithObjectsAndKeys:dateFont,NSFontAttributeName,nil];
    CGSize dateStringSize = [dateString boundingRectWithSize:maximumSize options:NSStringDrawingUsesFontLeading attributes:tdic context:nil].size;
    CGRect dateFrame = CGRectMake(10, 10, 300, dateStringSize.height);
    ticketsValidTime.frame = dateFrame;