c# - Help with a OleDB connection string for excel files

Question

The problem i'm having is that the data adapter is looking at only the first row in each column to determine the data type. In my case the first column "SKU" is numbers for the first 500 rows then I happen to have SKU's which are mixed numbers and letters. So what ends up happening is rows in the SKU column are left blank, but I still get the other information for each column row.

I believe it is the connection string that controls that and with my current settings it should work, however it is not.

Connection String:

conn.ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:UsersNickDesktopPricing2.xlsx" + @";Extended Properties=""Excel 12.0 Xml;HDR=Yes;IMEX=1;ImportMixedTypes=Text;TypeGuessRows=0""";

ImportMixedTypes=Text;TypeGuessRows=0

Should be the important keywords, look at 0 rows and just use text as the value types for everything.

The "bandaid" I have put on this is to make the first row in the spreadsheet a mixture of letters and numbers and specifically leave that row out in my query.

Answer 1

Unfortunately, you can't set ImportMixedTypes or TypeGuessRows from the connection string since those settings are defined in the registry. For the ACE OleDb driver, they're stored at

HKEY_LOCAL_MACHINESOFTWAREMicrosoftOffice14.0Access Connectivity EngineEnginesExcel

in the registry. So, you can simplify your connection string to:

conn.ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:UsersNickDesktopPricing2.xlsx;Extended Properties=""Excel 12.0 Xml;HDR=Yes;IMEX=1;""";

Once you set TypeGuessRows to 0 and ImportMixedTypes to Text in the registry, you should get the behavior you are expecting. You might, however, consider using a suitably large number like 1000 instead of zero if you find import performance to be less than ideal.