Develop Reference

Cannot parse some excel column

Good day!
I try to open and parse excel file into DataSet.
So, i use OleDbConnection:
if (_filePath.Substring(_filePath.LastIndexOf('.')).ToLower() == ".xlsx")
// strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source="
// + _filePath + ";Extended Properties=\"Excel 12.0;HDR=" + HDR + ";IMEX=0\"";
strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source="
+ _filePath + ";Extended Properties=\"Excel 12.0 Xml;HDR=" + HDR + ";IMEX=1;TypeGuessRows=0;ImportMixedTypes=Text;\"";
// strConn="Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + _filePath + ";Extended Properties=Excel 12.0;";
else
strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + _filePath + ";Extended Properties=\"Excel 8.0;HDR=" + HDR + ";IMEX=1\"";
But some column are empty!
The next column parses well (it with same data).
Can you tell me how to fix it?
Then i fill Dataset:
OleDbConnection conn = new OleDbConnection(strConn);
System.Data.DataSet dtSet;
System.Data.OleDb.OleDbDataAdapter oleCommand;
oleCommand = new System.Data.OleDb.OleDbDataAdapter("select * from [" + sheetName + "]", conn);
oleCommand.TableMappings.Add("Table", sheetName);
dtSet = new System.Data.DataSet();
oleCommand.Fill(dtSet);
oleCommand.Dispose();
conn.Close();
return dtSet.Tables[0];
But, some columns are empty!
May be, it happens because excel file has format:
Cell1--------------|Value1------------|
Cell2---|Cell3-----|Value2---|Value4--|
So, dataset fill columns :
Cell1---|-------|--Value1------|-----|
Cell2---|Cell3--|---Empty(!)---|Value4|
So, i need to get Empty(!) column.
About invalid data at column.
I copy and paste this column at right column- and it works!
But,i should use last format, not mine.
HDR="NO";

Maybe you ran into this error:
OleDB & mixed Excel datatypes : missing data
What's the value of 'HDR'? Take a look at the Datatypes of the Columns, maybe they are mixed.

Read Data from Excel using OLEDB

I read an excel file using OLEDB. Below is the code:
string conn;
conn = ("Provider=Microsoft.ACE.OLEDB.12.0;" +
("Data Source=" + _filename + ";" +
"Extended Properties=\"Excel 12.0;\""));
OleDbConnection oleDBCon = new OleDbConnection(conn);
oleDBCon.Open();
DataTable dt = oleDBCon.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
string SSQL = "SELECT * from [ Sheet1$ ]";
OleDbDataAdapter oleDA = new OleDbDataAdapter(SSQL, conn);
DataSet ds = new DataSet();
oleDA.Fill(ds);
DataTable _DtTable = ds.Tables[0];
oleDBCon.Close();
dataGridView1.DataSource = _DtTable;
foreach (DataRow rows in _DtTable.Rows)
{
string Description = rows[0].ToString();
string Code= rows[1].ToString();
textBox1.AppendText("Printing Description: " + Description + " and Code: " + Code + ",Date:" + DateTime.Now.ToString() + Environment.NewLine);
}
The excel file is as follows:
The data printed in textBox1 are:
Printing Description:Desc 2 and Code: Code 2,Date:20/12/2014 12:36:54 μμ
Printing Description: Desc 3 and Code: Code 3,Date:20/12/2014 12:36:54 μμ
So, my problem is that the 1st row of excel is going to the header of the Datatable. How can I avoid that (without adding any extra 1st row to excel)?

Just add "HDR=No" at the end of your connection string which means "No header row that indicates column but it contains data", then you will be able to fetch 1st row data also.
So your complete connection string would be
conn = ("Provider=Microsoft.ACE.OLEDB.12.0;" +
("Data Source=" + _filename + ";" +
"Extended Properties=\"Excel 12.0;\";HDR=No"));

Opening an Excel (created with EPPLUS) with OleDB

I have code from a colleague, this code creates a few excel sheets with Epplus. With my code I would like to add an database extract 10k+/- lines. Because of the large amount of data it takes too long with Epplus, because you need to write each cell. With OleDB it only takes a few seconds. But I can't open a previously created excel by Epplus with OleDB. Even with different connection strings.
This my code works perfect if you separate the two code blocks.
var excelPath = "C:\\test_" + DateTime.Today.ToString("yyyyMMdd_") + DateTime.Now.ToString("hh") + DateTime.Now.Minute.ToString() + ".xlsx";
using (ExcelPackage xlPackage = new ExcelPackage(new FileInfo(excelPath)))
{
ExcelWorksheet worksheet = xlPackage.Workbook.Worksheets.Add("Schedule V");
worksheet.Cell(1, 1).Value = "test";
xlPackage.Save();
xlPackage.Dispose();
}
var strCn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelPath + ";Extended Properties='Excel 12.0 Xml';";
using (OleDbConnection conn = new OleDbConnection(strCn))
{
conn.Open();
OleDbCommand cmd = new OleDbCommand();
cmd.Connection = conn;
cmd.CommandText = "CREATE TABLE [table1] (id INT, name VARCHAR, datecol DATE );";
cmd.ExecuteNonQuery();
cmd.CommandText = "INSERT INTO [table1](id,name,datecol) VALUES(1,'AAAA','2014-01-01');";
cmd.ExecuteNonQuery();
conn.Close();
}
I tried the following connection strings but they all give the same error:
OleDbException was unhandled, External table is not in the expected
format.
My diffrent connection string I tried:
var strCn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelPath + ";Extended Properties='Excel 12.0';";
var strCn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelPath + ";Extended Properties='Excel 12.0 Xml';";
var strCn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelPath + ";Extended Properties='Excel 12.0 Xml;HDR=YES';";
var strCn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelPath + ";Extended Properties='Excel 12.0 Xml;HDR=YES;IMEX=1';";
var strCn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelPath + ";Extended Properties='Excel 8.0;HDR=YES';";
var strCn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + excelPath + ";Extended Properties='Excel 8.0;HDR=Yes;IMEX=1';";
What am I doing wrong here?

I guess, it should be like this, rather than hardcoding you should use OleDbConnectionStringBuilder class
OleDbConnectionStringBuilder connectionStringBuilder = new OleDbConnectionStringBuilder();
connectionStringBuilder.Provider = "Microsoft.ACE.OLEDB.12.0";
connectionStringBuilder.DataSource = excelPath; // This is your Excel File Full Path
connectionStringBuilder.Add("Mode", "Read");
const string extendedProperties = "Excel 12.0;IMEX=1;HDR=YES";
connectionStringBuilder.Add("Extended Properties", extendedProperties);
String connectionString = connectionStringBuilder.ToString();
// Create connection object by using the preceding connection string.
using (var objConn = new OleDbConnection(connectionString))
{
// Open connection with the database.
objConn.Open();
// Do operations with your File here
}

I was getting this error consistently with .xlsx files created with EPPlus 4.0.4. I remembered this was working prior to upgrading to EPPlus 4.x. I downgraded to 3.1.3.3 and I no longer get this error.

The Microsoft Jet database engine cannot open the file ''.It is already opened exclusively by another user, or you need permission to view its data"

i am using OLEDB server to read excel file in my ASP.NET MVC project. then i m getting error
"The Microsoft Jet database engine cannot open the file ''.It is already opened exclusively by another user, or you need permission to view its data". same code with different comnnection string of CSV file is work fine but For Excel connectionString i am getting this error. is there anyone know the solution for this please.
My code is:
public JsonResult ImportCSVFiles()
{
HttpPostedFileBase hpf = null;
foreach (string file in Request.Files)
{
hpf = Request.Files[file] as HttpPostedFileBase;
}
string[] FileName;
string filename = hpf.FileName;
string DestinationPath = Server.MapPath("..") + "\\CSVFiles\\";
if (!Directory.Exists(DestinationPath))
{
Directory.CreateDirectory(DestinationPath);
if (System.IO.File.Exists(Server.MapPath("..") + "\\CSVFiles\\" + filename) == false)
{
hpf.SaveAs(DestinationPath + filename);
}
else
{
System.IO.File.Delete(Server.MapPath("..") + "\\CSVFiles\\" + filename);
hpf.SaveAs(DestinationPath + filename);
}
}
else
{
if (System.IO.File.Exists(Server.MapPath("..") + "\\CSVFiles\\" + filename) == false)
{
hpf.SaveAs(DestinationPath + filename);
}
else
{
System.IO.File.Delete(Server.MapPath("..") + "\\CSVFiles\\" + filename);
hpf.SaveAs(DestinationPath + filename);
}
}
bool isFirstRowHeader = true;
string header = isFirstRowHeader ? "Yes" : "No";
string path = "";
string pathOnly = Path.GetDirectoryName(DestinationPath);
string fileName = Path.GetFileName(DestinationPath + "\\" + filename);
string sql = #"SELECT * FROM [" + fileName + "]";
//using (OleDbConnection connection = new OleDbConnection(
// #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathOnly +
// ";Extended Properties=\"Text;HDR=" + header + "\""))
using (OleDbConnection connection = new OleDbConnection(
#"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathOnly +
";Extended Properties=\"Excel 8.0;HDR=Yes;IMEX=1\";"))
using (OleDbCommand command = new OleDbCommand(sql, connection))
using (OleDbDataAdapter adapter = new OleDbDataAdapter(command))
{
DataTable dataTable = new DataTable();
dataTable.Locale = CultureInfo.CurrentCulture;
adapter.Fill(dataTable);
}
}
commented connectionstring is for CSV file and CSV file works fine with same code.

I had the same problem with a program I was recently working on. My solution was to simply take out the extra bits from the connection string. I have no idea why it worked but since it worked for me, it might work for you. This is what your new connection string would look like:
using (OleDbConnection connection = new OleDbConnection(
#"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathOnly + ";"))
You actually might be able to keep the HDR=Yes bit just because I understand that you might need that to tell it there are headers and I don't think leaving it in would affect it.

Why is OleDB ignoring Excel cells?

Here's the setup:
I have an excel spreadsheet that has a very simple page. It looks like so:
I use the following connection string to access this file:
string.Format("Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties=\"Excel 8.0;HDR=NO\";", fn)
My function to access the file looks like:
try
{
string select = string.Format("SELECT * FROM [{0}$]", tab.PageName);
OleDbDataAdapter adapter = new OleDbDataAdapter(select, con);
DataSet ds = new DataSet();
adapter.Fill(ds, tab.PageName);
// DEBUG: Let's just see what it is getting...
for (int x = 0; x < 13; x++)
{
for (int y = 0; y < 3; y++)
{
Console.Write(ds.Tables[0].Rows[x][y].ToString() + "\t");
}
Console.WriteLine("");
}
}
catch
{ ... }
QUESTION
Why would the code NOT read some cells? Note that there is the text "Profit" at C5. I can read B5 just fine as "Revenue". I can read C6 just fine as an integer value. But Profit seems to vanish.
This isn't such a big problem with the header information, but entire blocks of real data refuse to be read. Instead it returns DBNull, even when the cell contains real, valid, usable data. The cells are all formatted exactly the same between cells that can read and cells that return DBNull.
I'm truly stumped!!!
Any thoughts?

new OleDbConnection("...TypeGuessRows=0;ImportMixedTypes=Text");
I have a hunch you may be experiencing a problem that I had previously.
Try adding those parameters to your connection string.

I was having trouble getting the other answer+comment to work. The only setting needed was the IMEX=1 but it must be nested in single quotes in the Extended Properties, so here's an example of exactly how to format the additional IMEX setting:
connection.ConnectionString =
#"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\somepath\somefile.xls;Extended Properties='Excel 8.0;IMEX=1';";

if (ObjFile.Extension == ".xls")
conn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + srcFilePath + ";" + "Extended Properties='Excel 8.0;HDR=YES;'";
if (ObjFile.Extension == ".xlsx")
conn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + srcFilePath + ";" + "Extended Properties='Excel 12.0 Xml;HDR=YES;IMEX=1';";
if (ObjFile.Extension == ".xlsm")
conn = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + srcFilePath + ";Extended Properties='Excel 12.0 Macro;HDR=No;IMEX=1';";