C# – How to get list of ONLY excel worksheet names in Excel using OLEDB; filter out non-worksheets that show up in metadata

cexceloledb

I have an issue getting worksheet names from an Excel spreadsheet using OLEDB. The problem is that when I use GetOleDbSchemaTable, the resulting DataTable has more than just the actual worksheet names; it has extra rows for "Tables" that I can only assume are used internally by Excel.

So for example, if I have a worksheet named myWorksheet, the code below might end up with a list that contains myWorksheet$, myWorksheet$PrintTable and myWorksheet$_. Only the first myWorksheet$ record is for the actual worksheet. The others are just garbage that I don't need. When you look at them in metadata they look just like regular tables, even with the type of TABLE.

For now I just manually filtered out anything with "$_" or "$Print" in the name, but who knows what other Excel feature might make these extra records turn up in a different format.

Does anyone know the best way to get ONLY actual worksheet names, and not these internal tables that aren't worksheets? Is there something in metadata that would differentiate them?

 private ArrayList getXlsWorksheetNames(OleDb.OleDbConnection conn)
    {
        ArrayList wsList = new ArrayList();
        DataTable schemaTable;

        try
        {
            conn.Open();
            schemaTable = conn.GetOleDbSchemaTable(OleDb.OleDbSchemaGuid.Tables, null);

            foreach (DataRow row in schemaTable.Rows)
            {
                //form.appendToResultsTxt("Adding worksheet to list: " + Environment.NewLine +
                //    "Name = " + row.Field<string>("TABLE_NAME") + "," + Environment.NewLine +
                //    "Type = " + row.Field<string>("TABLE_TYPE") + "," + Environment.NewLine + Environment.NewLine);
                wsList.Add(row.Field<string>("TABLE_NAME"));
            }
            conn.Close();
        }
        catch (Exception ex)
        {
            if (this.mode == Cps2TxtUtilModes.GUI_MODE)
            {
                this.form.appendToResultsTxt(ex.ToString());
            }
            throw;
        }

        return wsList;
    }

I read through the article at this link, but they don't seem to be doing anything differently than I am, and I don't see any filtering out of extra non-worksheet tables, so Microsoft doesn't seem to have provided the right answer.

http://support.microsoft.com/kb/318452

And I've also looked around alot of StackOverflow, like at the thread from the link below which was helpful, but doesn't solve this one problem.

Using Excel OleDb to get sheet names IN SHEET ORDER

Before anyone asks, I'd also like to say that I don't really have control over what features are used in the spreadsheet, so I can't just tell them "Don't turn on filtering" or "Don't use print tables".

Any ideas are much appreciated. Thanks!

Best Answer

The question is old, but for those who found it now, the skipping can be done as Jim found...

// skip those that do not end correctly
foreach (DataRow row in schemTable.Rows)
{
    string sheetName = row["TABLE_NAME"].ToString();
    if (!sheetName.EndsWith("$") && !sheetName.EndsWith("$'"))
        continue;
    Console.WriteLine(sheetName);
}

That is the wanted are or those that end with $ or those that end with $'.

Related Solutions

C# – Using Excel OleDb to get sheet names IN SHEET ORDER

Can you not just loop through the sheets from 0 to Count of names -1? that way you should get them in the correct order.

Edit

I noticed through the comments that there are a lot of concerns about using the Interop classes to retrieve the sheet names. Therefore here is an example using OLEDB to retrieve them:

/// <summary>
/// This method retrieves the excel sheet names from 
/// an excel workbook.
/// </summary>
/// <param name="excelFile">The excel file.</param>
/// <returns>String[]</returns>
private String[] GetExcelSheetNames(string excelFile)
{
    OleDbConnection objConn = null;
    System.Data.DataTable dt = null;

    try
    {
        // Connection String. Change the excel file to the file you
        // will search.
        String connString = "Provider=Microsoft.Jet.OLEDB.4.0;" + 
          "Data Source=" + excelFile + ";Extended Properties=Excel 8.0;";
        // Create connection object by using the preceding connection string.
        objConn = new OleDbConnection(connString);
        // Open connection with the database.
        objConn.Open();
        // Get the data table containg the schema guid.
        dt = objConn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);

        if(dt == null)
        {
           return null;
        }

        String[] excelSheets = new String[dt.Rows.Count];
        int i = 0;

        // Add the sheet name to the string array.
        foreach(DataRow row in dt.Rows)
        {
           excelSheets[i] = row["TABLE_NAME"].ToString();
           i++;
        }

        // Loop through all of the sheets if you want too...
        for(int j=0; j < excelSheets.Length; j++)
        {
            // Query each excel sheet.
        }

        return excelSheets;
   }
   catch(Exception ex)
   {
       return null;
   }
   finally
   {
      // Clean up.
      if(objConn != null)
      {
          objConn.Close();
          objConn.Dispose();
      }
      if(dt != null)
      {
          dt.Dispose();
      }
   }
}

Extracted from Article on the CodeProject.

Excel – OleDB & mixed Excel datatypes : missing data

Using .Net 4.0 and reading Excel files, I had a similar issue with OleDbDataAdapter - i.e. reading in a mixed data type on a "PartID" column in MS Excel, where a PartID value can be numeric (e.g. 561) or text (e.g. HL4354), even though the excel column was formatted as "Text".

From what I can tell, ADO.NET chooses the data type based on the majority of the values in the column (with a tie going to numeric data type). i.e. if most of the PartID's in the sample set are numeric, ADO.NET will declare the column to be numeric. Therefore ADO.Net will attempt to cast each cell to a number, which will fail for the "text" PartID values and not import those "text" PartID's.

My solution was to set the OleDbConnection connectionstring to use Extended Properties=IMEX=1;HDR=NO to indicate this is an Import and that the table(s) will not include headers. The excel file has a header row, so in this case tell ado.net not to use it. Then later in the code, remove that header row from the dataset and voilà you have mixed data type for that column.

string sql = "SELECT F1, F2, F3, F4, F5 FROM [sheet1$] WHERE F1 IS NOT NULL";

OleDbConnection connection = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + PrmPathExcelFile + @";Extended Properties=""Excel 8.0;IMEX=1;HDR=NO;TypeGuessRows=0;ImportMixedTypes=Text""");

OleDbCommand cmd = new OleDbCommand(sql, connection);
OleDbDataAdapter da = new OleDbDataAdapter(cmd);

DataSet ds = new DataSet();
ds.Tables.Add("xlsImport", "Excel");
da.Fill(ds, "xlsImport");

// Remove the first row (header row)
DataRow rowDel = ds.Tables["xlsImport"].Rows[0];
ds.Tables["xlsImport"].Rows.Remove(rowDel);

ds.Tables["xlsImport"].Columns[0].ColumnName = "LocationID";
ds.Tables["xlsImport"].Columns[1].ColumnName = "PartID";
ds.Tables["xlsImport"].Columns[2].ColumnName = "Qty";
ds.Tables["xlsImport"].Columns[3].ColumnName = "UserNotes";
ds.Tables["xlsImport"].Columns[4].ColumnName = "UserID";

connection.Close();

// now you can use LINQ to search the fields

    var data = ds.Tables["xlsImport"].AsEnumerable();
    var query = data.Where(x => x.Field<string>("LocationID") == "COOKCOUNTY").Select(x =>
                new Contact
                {
                    LocationID= x.Field<string>("LocationID"),
                    PartID = x.Field<string>("PartID"),
                    Quantity = x.Field<string>("Qty"),
                    Notes = x.Field<string>("UserNotes"),
                    UserID = x.Field<string>("UserID")
                });

Best Answer

Related Solutions

C# – Using Excel OleDb to get sheet names IN SHEET ORDER

Excel – OleDB & mixed Excel datatypes : missing data

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