oledb {"操作必须使用一个可更新的查询。"} 解决
@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fileName
+ ";Mode=ReadWrite;Extended Properties=\"Excel 12.0;HDR=YES;IMEX=0\";Jet OLEDB:Engine Type=37";
"IMEX=1;" tells the driver to always read "intermixed" (numbers, dates, strings etc) data columns as text. Note that this option might affect excel sheet write access negative. See more from here .
http://tips.pjmsn.me.uk/t0003.htm
该字串为2007以上excel使用.