Problem in loading Excel file.

[Alpha Zero]

Hi!
I am making connection to excel.
But all fields which are not of string type are being read as null.
---------------code-------------------------------
excelConnection = new System.Data.OleDb.OleDbConnection(
@"provider=Microsoft.Jet.OLEDB.4.0;data source="+file+"; Extended
Properties=\"Excel 8.0;HDR=No\"");

excelConnection.Open();

//Guid guid = new Guid();

System.Data.DataTable schema =
excelConnection.GetOleDbSchemaTable(System.Data.Ol eDb.OleDbSchemaGuid.Tables
,null);
string firstSheetName;

firstSheetName = schema.Rows[0]["TABLE_NAME"].ToString();

excelCommand = new System.Data.OleDb.OleDbCommand( "select * from
["+firstSheetName+"A:AL]", excelConnection);

excelCommand.CommandType = CommandType.Text;
excelDa = new OleDbDataAdapter(excelCommand);

excelDs = new System.Data.DataSet();

excelDa.Fill(excelDs);

excelFileTable = excelDs.Tables[0];

DataRow dataRow;

dataRow = excelFileTable.Rows[i];

---------------code-------------------------------

All elemetns of dataRow which are not string are null.

Any Idea?

Thanks.