asp.net读取Excel文件，连接有两个版本.xls与.xlsx，参考：
| Extension | ConnectionString |
| xls | Provider=Microsoft.Jet.OLEDB.4.0;Data Source=[ExcelFilePath];Extended Properties=”Excel 8.0;HDR=YES;IMEX=1” |
| xlsx | Provider=Microsoft.ACE.OLEDB.12.0;Data Source=[ExcelFilePath];Extended Properties=Excel 12.0 Xml;HDR=YES;IMEX=1 |
实例参考视频：
http://www.cnblogs.com/insus/articles/1425052.html