#pragma mark -- UITableViewDelegate

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {

    NSNumber *height = self.heightArray[indexPath.row];

    //含有中文需要加一行字体的高度，也就是 font

    return height.floatValue;

}

//存储计算出来的高度

- (NSMutableArray *)heightArray {

    if (!_heightArray) {

        _heightArray = [NSMutableArray arrayWithCapacity:];

        for (int i = ; i < self.dataSource.count; i++) {

            NSString *str = [NSString stringWithFormat:@"%@",_dataSource[i]];

            CGFloat height = [HeightModel calculate:str];

            [_heightArray addObject:[NSNumber numberWithFloat:height]];

        }

    }

    return _heightArray;

}

//计算文字高度

+ (CGFloat)calculate:(NSString *)text {

    CGSize maxSize = CGSizeMake(KScreenWidth, MAXFLOAT);

    CGSize trueSize = [text boundingRectWithSize:maxSize

                                         options:

                       (NSStringDrawingUsesFontLeading | NSStringDrawingUsesLineFragmentOrigin)

                                      attributes:@{NSFontAttributeName:[UIFont systemFontOfSize:]}

                                         context:nil].size;

    NSLog(@"%f",trueSize.height);

    return trueSize.height+;

}