//根据文字获取size
- (CGSize)getSizeWithstring:(NSString *)string
{
CGSize maxSize = CGSizeMake(320, 320);
NSDictionary *dict = @{NSFontAttributeName : [UIFont systemFontOfSize:11.0]};
CGSize size = [string boundingRectWithSize:maxSize options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingTruncatesLastVisibleLine | NSStringDrawingUsesFontLeading attributes:dict context:nil].size;
return size;
}