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C# OleDbDataAdapter return null values in cases excel cell is not in Correct data type

I wanna read data from excel spreadsheet and insert them into Access data base(.accdb). there is a problem with data format in excel. some cells are in incorrect type. Correct format for example is 99999 and incorrect is 9999-888 . because of dash(-) ole data adapter return null values instead of text. how should i get whole cell block?
I have tried change the cell format of excel from General to Text but the problem is still available.
thanks
string connectionStringExcel = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + openFileDialog1.FileName + ";Extended Properties=Excel 12.0;";
using (OleDbConnection connectionExcel = new OleDbConnection(connectionStringExcel))
{
OleDbDataAdapter daExcel = new OleDbDataAdapter(#"SELECT * FROM [priclist$]", connectionExcel);
DataTable dtExcel = new DataTable();
daExcel.Fill(dtExcel);
dataGridView1.DataSource = dtExcel;
}

By default, the Microsoft.ACE.OLEDB.12.0 provider tries to determine variable type for each column, and assumes the majority type is the column type.
You can override this behaviour by specifying IMEX=1 in the connection string, which uses text when encountering mixed-field types instead of setting the ones not matching the type to Null. Then you can handle the values in your C# code:
string connectionStringExcel = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + openFileDialog1.FileName + ";Extended Properties=Excel 12.0;IMEX=1;";
Read more about the IMEX property by following the link in the comment below

I use the following code to transfer data from Excel to datagrid :
private void btnreadExcell_MouseDown(object sender, MouseButtonEventArgs e)
{
try
{
string filePath = string.Empty;
string fileExt = string.Empty;
OpenFileDialog ofd = new OpenFileDialog();
ofd.Filter = "Excel Files|*.xls;*.xlsx;*.xlsm";
Nullable<bool> result = ofd.ShowDialog();
if (result == true)//if there is a file choosen by the user
{
filePath = ofd.FileName;//get the path of the file
try
{
DataTable dtExcel = new DataTable();
dtExcel = ReadExcel(filePath, fileExt);//read excel file
// dataGrid.Visible = true;
dataGrid.ItemsSource = dtExcel.DefaultView;
datagridheader();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message.ToString());
}
}
con.Close();
}
catch { MessageBox.Show("error");}
}
public DataTable ReadExcel(string fileName, string fileExt)
{
DataTable dtexcel = new DataTable();
try
{
string conn = string.Empty;
if (fileExt.CompareTo(".xls") == 0)//compare the extension of the file
conn = #"provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + fileName + ";Extended Properties='Excel 8.0;HRD=Yes;IMEX=1';";//for below excel 2007
else
conn = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fileName + ";Extended Properties='Excel 12.0;HDR=Yes;IMEX=1';";//for above excel 2007
using (OleDbConnection con = new OleDbConnection(conn))
{
try
{
OleDbDataAdapter oleAdpt = new OleDbDataAdapter("select * from [Sheet1$]", con);//here we read data from sheet1
oleAdpt.Fill(dtexcel);//fill excel data into dataTable
}
catch (Exception ex)
{
MessageBox.Show(ex.Message.ToString());
}
}
conn.Clone();
}
catch { MessageBox.Show("error"); }
return dtexcel;
}

My error has been Solved!!! with set both IMEX=1 And HDR=No. if you have changed your header in excel files(first row) use below code to solve same problem as i asked above.
try this
(two connection string have same meaning)
string connectionStringExcel = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + openFileDialog1.FileName + ";Extended Properties='Excel 12.0;HDR=No;IMEX=1';"
Or
string connectionStringExcel = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" +"T13970524.xlsx" + ";Extended Properties=\"Excel 12.0 Xml;HDR=No;IMEX=1\";";

Format of the initialization string does not conform to specification starting at index 129

I'm new to C# & I believe it is a syntax error or a connection error
Here is the code that it highlights as the error.
private void btnLoadExcel_Click(object sender, EventArgs e)
{
String PathConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + textBox1.Text + ";Extended Properties='Excel 8,0;HDR=yes; \";";
OleDbConnection conn = new OleDbConnection(PathConn);
OleDbDataAdapter myDataAdaptor = new OleDbDataAdapter("select 8 form [" + TBSheet.Text + "$]", conn);
DataTable dt = new DataTable();
myDataAdaptor.Fill(dt);
dataGridView1.DataSource = dt;
}

I would suggest that you debug the code and have a look at the character at position 129 - the error will be there.
That said, it does look like you're mixing a single quote and double quote in your "Extended Properties" part - try something like this:
"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + textBox1.Text + ";Extended Properties=\"Excel 8.0;HDR=yes\";";
(I've also changed "8,0" to "8.0", as indicated on connectionstrings.com, though it might be that either works)

C# GetOleDbSchemaTable. Name of first Excel Worksheet and its columns

try
{
string connectionString = string.Empty;
if (Path.GetExtension(fileName) == ".xlsx")
{
connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fileName +
";Extended Properties=Excel 12.0;";
}
else
{
Debug.Print(connectionString);
connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Path.Combine(Server.MapPath("~/Content"), fileName) + ";Extended Properties=Excel 8.0;";
//connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + Path.Combine(Server.MapPath("~/Content"), fileName) + ";Extended Properties=\"Excel 12.0 Xml;HDR=YES\"";
}
OleDbCommand selectCommand = new OleDbCommand();
OleDbConnection connection = new OleDbConnection();
OleDbDataAdapter adapter = new OleDbDataAdapter();
connection.ConnectionString = connectionString;
if (connection.State != ConnectionState.Open)
connection.Open();
//connection.Get
DataTable dtSchema = connection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
}
catch (Exception ex)
{
Debug.Print(ex.ToString());
}
connection.Open() seems to be connecting just fine. Now I have gotten a dtSchema Data Table object. I am needing to get the name of the Excel worksheet or worksheets that were gotten if any. I am also scanning the object to find out where the column names are. There is supposed to be some columns in the schema. Is it documented where the columns are?
When I do some output in my immediate window:
dtSchema.Columns[0].ToString()
"TABLE_CATALOG"
dtSchema.Columns[1].ToString()
"TABLE_SCHEMA"
dtSchema.Columns[2].ToString()
"TABLE_NAME"
dtSchema.Columns[3].ToString()
"TABLE_TYPE"
These are not the column names of the first worksheet, which is what I am looking for mainly the name of the first worksheet and its columns.
Thank you for posting..

If you want to look for column names. See the resultant COLUMN_NAME column
DataTable dtCols = this.connection.GetSchema("Columns");
TABLE_NAME is also helpful for your case to identify the Sheet.

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;

Operation must use an updateable query when updating excel sheet

I am getting this error when trying to update excel sheet :
Server Error in '/ReadExcelData_Csharp' Application.
Operation must use an updateable query.
and here is the code that i am using :
querys = "UPDATE [Sheet1$] "+"SET [Number]=" +s.Trim()+ " WHERE [Number]=" + s2.Trim() ;
objcmc = new OleDbCommand(querys, conn);
objcmc.ExecuteNonQuery();
any help will be appreciated .
and here is the connection i used :
if (strFileType.Trim() == ".xls")
{
connString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + strNewPath + ";Extended Properties=\"Excel 8.0;HDR=Yes;IMEX=2\"";
}
else if (strFileType.Trim() == ".xlsx")
{
connString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + strNewPath + ";Extended Properties=\"Excel 12.0;HDR=Yes;IMEX=2\"";
}

Remove the IMEX=2 (or IMEX=1) from the connection string and it will work. I have tested this crazy solution several times and removing the IMEX for some strange reason seems to do the trick (at least for xlsx files).
The following code works:
static void Main(string[] args)
{
string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + "d:\\temp\\customers.xlsx" + ";Extended Properties=\"Excel 12.0;ReadOnly=False;HDR=Yes;\"";
string selectString = "INSERT INTO [Customers$](Id,Company) VALUES('12345', 'Acme Inc')";
OleDbConnection con = new OleDbConnection(connectionString);
OleDbCommand cmd = new OleDbCommand(selectString, con);
try
{
con.Open();
cmd.ExecuteNonQuery();
Console.WriteLine("Success");
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
finally
{
con.Dispose();
}
Console.ReadLine();
}
}
Thanks to RobertNet from social.msdn.microsoft.com

I used the solution provided above and removed the IMEX=2 or IMEX=1 string from the connection string. But this was not enough. In my case, the solution needed an additional work around.
But in my data base I actually needed the IMEX - because my column had mixed data types, some double values some string values. When I remove IMEX =1, I get the a runtime exception "Unable to cast object of type" because it automatically selects the column data type based on the most popular value in the column and then fails to cast the values which are not of the selected type.
I worked around this issue by changing my double and int values to string values (added a ' in the beginning of the cell value manually in excel) and removed the IMEX from the connection string. and then this solved the issue.

In my case,I changed ConnectionString and then this solved the issue.
I removed ReadOnly=False;HDR=Yes; parametes in connectionString
string _connectionString = string.Format("Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties=\"Excel 12.0;\";", pathToExcelFile);