TP5的PHPExcel包实现导入导出功能

将下载好的PHPExcel文件夹跟PHPExcel放置在框架中的Vendor目录下，注意目录的结构，按照我的代码来基本上直接引用就能使用。

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     目录           0  2019-01-08 13:55  PHPExcel\
     目录           0  2019-01-08 13:55  PHPExcel\PHPExcel\
     文件       31533  2018-12-20 14:44  PHPExcel\PHPExcel.php
     文件        2884  2018-12-20 14:44  PHPExcel\PHPExcel\Autoloader.php
     目录           0  2019-01-08 13:55  PHPExcel\PHPExcel\CachedobjectStorage\
     文件        9548  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\APC.php
     文件       10594  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\Cachebase.php
     文件        6776  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\DiscISAM.php
     文件        3484  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\ICache.php
     文件        4862  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\Igbinary.php
     文件       10709  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\Memcache.php
     文件        3800  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\Memory.php
     文件        4333  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\MemoryGZip.php
     文件        4319  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\MemorySerialized.php
     文件        6451  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\PHPTemp.php
     文件       10363  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\SQLite.php
     文件       11230  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\SQLite3.php
     文件        9945  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorage\Wincache.php
     文件        7888  2018-12-20 14:44  PHPExcel\PHPExcel\CachedobjectStorageFactory.php
     目录           0  2019-01-08 13:55  PHPExcel\PHPExcel\CalcEngine\
     文件        2297  2018-12-20 14:44  PHPExcel\PHPExcel\CalcEngine\CyclicReferenceStack.php
     文件        4173  2018-12-20 14:44  PHPExcel\PHPExcel\CalcEngine\Logger.php
     目录           0  2019-01-08 13:55  PHPExcel\PHPExcel\Calculation\
     文件      202013  2018-12-20 14:44  PHPExcel\PHPExcel\Calculation.php
     文件       33331  2018-12-20 14:44  PHPExcel\PHPExcel\Calculation\Database.php
     文件       69069  2018-12-20 14:44  PHPExcel\PHPExcel\Calculation\DateTime.php
     文件      110732  2018-12-20 14:44  PHPExcel\PHPExcel\Calculation\Engineering.php
     文件        1561  2018-12-20 14:44  PHPExcel\PHPExcel\Calculation\Exception.php
     文件        1467  2018-12-20 14:44  PHPExcel\PHPExcel\Calculation\ExceptionHandler.php
     文件      108945  2018-12-20 14:44  PHPExcel\PHPExcel\Calculation\Financial.php
     文件       26921  2018-12-20 14:44  PHPExcel\PHPExcel\Calculation\FormulaParser.php
............此处省略283个文件信息