Connection strings for Excel 2007
Providers to use when connecting to Excel 2007
1、ACE OLEDB 12.0
2、.NET Framework Data Provider for OLE DB(OleDbConnection)
3、.NET xlReader for Microsoft Excel(ExcelConnection)
ACE OLEDB 12.0
This driver was released with Office 2007. It is possible to use the Microsoft.ACE.OLEDB.12.0 to connect to older .xls (Excel 97-2003) workbooks as well.
Xlsx files
This one is for connecting to Excel 2007 files with the Xlsx file extension. That is the Office Open XML format with macros disabled.
Provider=Microsoft.ACE.OLEDB.12.0;Data Source=c:\myFolder\myExcel2007file.xlsx;Extended Properties="Excel 12.0 Xml;HDR=YES";
"HDR=Yes;" indicates that the first row contains columnnames, not data. "HDR=No;" indicates the opposite.
Treating data as text
Use this one when you want to treat all data in the file as text, overriding Excels column type "General" to guess what type of data is in the column.
Provider=Microsoft.ACE.OLEDB.12.0;Data Source=c:\myFolder\myExcel2007file.xlsx;Extended Properties="Excel 12.0 Xml;HDR=YES;IMEX=1";
If you want to read the column headers into the result set (using HDR=NO even though there is a header) and the column data is numeric, use IMEX=1 to avoid crash.To always use IMEX=1 is a safer way to retrieve data for mixed data columns. Consider the scenario that one Excel file might work fine cause that file's data causes the driver to guess one data type while another file, containing other data, causes the driver to guess another data type. This can cause your app to crash.
Xlsb files
This one is for connecting to Excel 2007 files with the Xlsb file extension. That is the Office Open XML format saved in a binary format. I e the structure is similar but it's not saved in a text readable format as the Xlsx files and can improve performance if the file contains a lot of data.
Provider=Microsoft.ACE.OLEDB.12.0;Data Source=c:\myFolder\myBinaryExcel2007file.xlsb;Extended Properties="Excel 12.0;HDR=YES";
Xlsm files
This one is for connecting to Excel 2007 files with the Xlsm file extension. That is the Office Open XML format with macros enabled.
Provider=Microsoft.ACE.OLEDB.12.0;Data Source=c:\myFolder\myExcel2007file.xlsm;Extended Properties="Excel 12.0 Macro;HDR=YES";
.NET Framework Data Provider for OLE DB
Bridging to ACE OLEDB 12.0
This is just one connection string sample for the wrapping OleDbConnection class that calls the underlying OLEDB provider. See respective OLE DB provider for more connection strings to use with this class.
Provider=Microsoft.ACE.OLEDB.12.0;Data Source=c:\myFolder\myExcel2007file.xlsx;Extended Properties="Excel 12.0 Xml;HDR=YES";
.NET xlReader for Microsoft Excel
Excel file with header row
Data Source =c:\myExcelFile.xlsx;HDR=yes;Format=xlsx;
Excel file without header row
Data Source =c:\myExcelFile.xlsx;HDR=no;Format=xlsx;