c# Excel skipping first row? - c#

I'm importing an xls file using OleDbCommand to a ds. Problem I'm having is during the foreach on my ds its skipping for first row. I can't figure out why. Any suggestions?
cmd.CommandText = string.Format("SELECT * FROM [{0}$]", worksheetName);
conn.Open();
var adapter = new OleDbDataAdapter();
var ds = new DataSet();
adapter.SelectCommand = cmd;
adapter.Fill(ds);
var table = ds.Tables[0];
foreach(DataRow row in table.Rows){ // rest of my code }

Change the connection string (as mentioned in comment) from:
string cnn = string.Format(
"Provider=Microsoft.ACE.OLEDB.12.0;" +
"data source={0}{1}{2};" +
"Extended Properties=Excel 8.0;",
fileLocation, fileName, fileExtension);
to:
string cnn = string.Format(
"Provider=Microsoft.ACE.OLEDB.12.0;" +
"data source={0}{1}{2};" +
"Extended Properties=Excel 8.0;HDR=No",
fileLocation, fileName, fileExtension);

Check your connection string. Most likely it contains:
HDR=Yes
which indicates that first row is a header

Maybe you've told it to skip first row. I remember a property that sounds something like FirstRowIsHeader. I think if that is set to true, then it skips. this can be changed at point you create your connection

Related

Updating excel values in data grid view on certain condition

I need to fetch a row value from an excel sheet in data grid view in winform.
I’m able to display the entire excel sheet in the datagridview. But, I need to display particular rows in the grid based on a current date condition.
public DataTable ReadExcel2(string fileName, string fileExt)
{
string connectionstring ;
DataTable dtexcel2 = new DataTable();
connectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fileName + ";Extended Properties='Excel 12.0;HDR=YES';";
OleDbConnection connection = new OleDbConnection(connectionstring);
OleDbCommand oconn = new OleDbCommand("Select * From [POSFailures$] WHERE Date=#date");
oconn.Connection = connection;
try
{
oconn.Parameters.AddWithValue("#date", DateTime.Now.ToString("MM/dd/yyyy"));
connection.Open();
OleDbDataAdapter sda = new OleDbDataAdapter(oconn);
sda.Fill(dtexcel2);
connection.Close();
}
catch (Exception)
{
}
return dtexcel2;
}
Thanking you in advance
What seems to be happening here is that the Date parameter is not being honored, as you are getting back all of the rows. So, I used Google to figure out how to properly add parameters when using OleDbConnection. I found this:
The OLE DB .NET Provider does not support named parameters for passing parameters to an SQL statement
Source: https://learn.microsoft.com/en-us/dotnet/api/system.data.oledb.oledbcommand.parameters?redirectedfrom=MSDN&view=netframework-4.8#System_Data_OleDb_OleDbCommand_Parameters
Using the example on that page, try changing your code to this:
string connectionstring;
DataTable dtexcel2 = new DataTable();
connectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fileName + ";Extended Properties='Excel 12.0;HDR=YES';";
OleDbConnection connection = new OleDbConnection(connectionstring);
OleDbCommand command = new OleDbCommand("Select * From [POSFailures$] WHERE Date = ?");
command.Parameters.Add(new OleDbParameter(DateTime.Now.ToString("MM/dd/yyyy"), OleDbType.Date));
command.Connection = connection;
try
{
connection.Open();
OleDbDataAdapter sda = new OleDbDataAdapter(command);
sda.Fill(dtexcel2);
connection.Close();
}
catch (Exception)
{
}
Please note that i've not tested this, so I can't promise it will work. But, the main point is... the answer is out there! You just need to go looking for it.

Reading Excel File using C#

I am new to C# and I am trying to read an excel file with the following code
string conStr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelFilePath +
";Extended Properties=Excel 12.0;";
using (OleDbConnection connection = new OleDbConnection(conStr))
{
connection.Open();
OleDbCommand command = new OleDbCommand("select * from [Sheet1$]", connection);
using (OleDbDataReader dr = command.ExecuteReader())
{
while (dr.Read())
{
var row1Col0 = dr[0];
Console.WriteLine(row1Col0);
}
}
}
I get the following error:
Sheet1$' is not a valid name. Make sure that it does not include invalid characters or punctuation and that it is not too long.
Can anyone tell me whats I am doing wrong?
The name of excel sheet is sheet.xlsx
Thanks
The sheet name might not be the same as the filename, you can get the first sheet name by doing the following
First, get the schema
DataTable dtSchema = connection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
Then get the first sheets name
var sheetName = dtSchema.Rows[0]["TABLE_NAME"].ToString();
After you get your command, you can then fill a dataset and work with it's .Rows collection
var myDataSet = new DataSet();
command.Fill(myDataSet);
The sheetname is this

in C# using oledb connection string how to Convert Scientific Notation to text strings?

I have a set of data that is downloaded as a Excel file using OLEDB connection string like so:
4552
3.00E+03
3.00E+22
3F45
3.00E+99
DD56677
37
Excel automatically thinks that 3E03, 3E22 and 3E99 are numbers and makes them look like above..
how to get it as a string ?
my code is
DataTable dataTable = new DataTable();
strExcelConn = "Provider=Microsoft.Jet.OLEDB.4.0;"
+ "Data Source=" + strFilePath + ";"
+ "Extended Properties='Excel 8.0;HDR=" + header + ";IMEX=1;TypeGuessRows=0;ImportMixedTypes=Text'";
OleDbConnection connection = new OleDbConnection(strExcelConn);
using (OleDbCommand command = new OleDbCommand())
using (OleDbDataAdapter adapter = new OleDbDataAdapter(command))
{
command.Connection = connection;
//Check if the Sheet Exists
connection.Open();
DataTable dtExcelSchema;
//Get the Schema of the WorkBook
dtExcelSchema = connection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
connection.Close();
connection.Open();
DataSet ds = new DataSet();
string SheetName = dtExcelSchema.Rows[0]["TABLE_NAME"].ToString();
command.CommandText = "SELECT * From [" + SheetName + "]";
adapter.SelectCommand = command;
adapter.Fill(dataTable);
connection.Close();
}
please can any one help me to get this colum as a string
Have a look at this StackOverflow question entitled How to convert a string containing an exponential number to decimal and back to string.
They use the decimal.Parse(someMoneyVar, NumberStyles.Any) method to do the conversion.
Select Excel Columns by name in your query and cast your required columns to a string using CStr(<columnName>)

OleDBException when reading an open excel file

I have an excel file and an oledb connection to it. When reading data while file is opened in windows, it throws the following error (at Adapter.Fill method).
However, the code runs fine when file is not opened manually.
private System.Data.DataSet GetExcelData()
{
// Create new DataSet to hold information from the worksheet.
System.Data.DataSet objDataset1 = new System.Data.DataSet();
DataTable dt = new DataTable();
try
{
string path = ConfigurationManager.AppSettings["ExcelFilePath"];
//string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + ";Extended Properties=Excel 12.0;";
string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + ";Extended Properties=\"Excel 12.0 Xml;HDR=YES;IMEX=1;\"";
OleDbConnection objConn = new OleDbConnection(connectionString);
objConn.Open();
//String strConString = "SELECT * FROM [Data Version5.2$A2:ZZ] where [Status] = 'aa'";//Status
String strConString = "SELECT * FROM [Data Version5.2$A2:ZZ] where [Status] IS NULL OR [Status]='SubReport'";//Status SubReport
OleDbCommand objCmdSelect = new OleDbCommand(strConString, objConn);
OleDbDataAdapter objAdapter1 = new OleDbDataAdapter();
// Pass the Select command to the adapter.
objAdapter1.SelectCommand = objCmdSelect;
// Fill the DataSet with the information from the work sheet.
objAdapter1.Fill(objDataset1, "ExcelData");
objConn.Close();
}
catch (Exception ex)
{
throw ex;
}
return objDataset1;
}
The error message is
Assuming you don't need to write to the file, try adjusting your connection string to include the read only mode (Mode=Read). I have that in all of mine (where I don't need to write to the file) and I've never had a problem reading from workbooks that are already open:
string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" +
path + ";Mode=Read;Extended Properties=\"Excel 12.0 Xml;HDR=YES;IMEX=1;\"";
I also don't tend to read Excel files as XML, so the Extended Properties for my connection strings are Excel 12.0;HDR=YES;IMEX=1;

Im having difficulty setting my OleDb connection

Hi there I am trying to establish a connection to a data source and extract the information and display it in a grid view. The problem is that i always get null value for ada. Is it possible to have mistyped the query or is there something wrong with the adapter?
Furthermore I am using the myInt variable to insert different data sources because i hav to process more than one file, maybe this could be problematic as well.
try
{
//establish connectioin
OleDbConnection conn = new OleDbConnection(("provider=Microsoft.Jet.OLEDB.4.0; " + ("data source=" + myInt + ";" + "Extended Properties=Excel 8.0;")));
OleDbDataAdapter ada = new OleDbDataAdapter("SELECT * FROM MarkingSheet$]", conn);
DataSet ds = new DataSet();
ada.Fill(ds);
dataGridView1.DataSource = ds.Tables[0].DefaultView;
conn.Close();
}
ANSWER
Thats what worked for me
OleDbConnection conn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + myPath + ";Excel 12.0;HDR=YES;"); ;
conn.Open();
OleDbDataAdapter ada = new OleDbDataAdapter("select * from [Marking Sheet$]", conn); ;
DataSet ds = new DataSet();
ada.Fill(ds);
Change the sql to
"SELECT * FROM [MarkingSheet$]"
since there's a missing opening bracket.
The Fault in your code is that you havent opened a connection when you attempt to fill the Adapter. Your SQL Statement is also wrong. You may also wan wish to bind the DataTable to the DataGridView too like this :-
try
{
OleDbConnection conn = new OleDbConnection(("provider=Microsoft.Jet.OLEDB.4.0; " + ("data source=" + myInt + ";" + "Extended Properties=Excel 8.0;")));
OleDbDataAdapter ada = new OleDbDataAdapter("SELECT * FROM [MarkingSheet$]", conn);
DataSet ds = new DataSet();
conn.Open();
ada.Fill(ds.Tables[0]);
conn.Close();
BindingSource bs = new BindingSource();
bs.Datasource = ds.Tables[0];
dataGridView1.DataSource = bs;
}
catch(OledbException x)
{
// Handle Exception
}
EDIT **
Try Changing your connection string to :-
string connString = "provider=Microsoft.Jet.OLEDB.4.0;Data source=" + myInt + ";Extended Properties=Excel 8.0;HDR=Yes;IMEX=1\";";

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