access databse into datagridview

rajulama

Hello everyone, I just wonder what's wrong with my code. Actually I want to use openfiledialog to locate an access database file and then display it in datagridview. I used following connection string:

Dim sConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=;Data Source=" & fi.DirectoryName

and following to call the table

Dim objCmdSelect As New OleDbCommand("select * from table1" & fi.Name, objConn)

But I get the famous 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." But neither by database is open nor its password protected. Please help me resolving this problem

Christian Graus

I suggest you google for a tool which tells you what process has a file open. I know such a tool exists. It's plain the file is open, you need to work out why.

Christian Graus Driven to the arms of OSX by Vista. "I am new to programming world. I have been learning c# for about past four weeks. I am quite acquainted with the fundamentals of c#. Now I have to work on a project which converts given flat files to XML using the XML serialization method" - SK64 ( but the forums have stuff like this posted every day )

Lost User

Are you viewing the contents of table1 in MS Access while debugging? If so, MS Access is the one that's locking the database :(

I are troll :)

rajulama

thanks for your suggestions but I think you misunderstood my problem. Following is complete code and its not working:

If OpenFileDialog1.ShowDialog(Me) = DialogResult.OK Then
Dim fi As New FileInfo(OpenFileDialog1.FileName)
Dim sConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=;Data Source=" & fi.DirectoryName
Dim objConn As New OleDbConnection(sConnectionString)
Dim objDataSet As DataSet = New DataSet()
objConn.Open()
Dim objCmdSelect As New OleDbCommand("select * from [Joint Restraint Assignments]" & fi.Name, objConn)
Dim objAdapter1 As New OleDbDataAdapter
objAdapter1.SelectCommand = objCmdSelect
objAdapter1.Fill(objDataSet, "test")
DataGridView1.DataSource = objDataSet.Tables(0).DefaultView
objConn.Close()
End If

I just wonder what's wrong with this code, in particular when i want to read access database file.

rajulama

thanks. no i m not. the access database as well as the table is not open.

Christian Graus

Ok, why do you need a fileinfo object ? I suspect that's what's locking your file. I did not misunderstand, your file is locked, if you like it or not.

Christian Graus Driven to the arms of OSX by Vista. "I am new to programming world. I have been learning c# for about past four weeks. I am quite acquainted with the fundamentals of c#. Now I have to work on a project which converts given flat files to XML using the XML serialization method" - SK64 ( but the forums have stuff like this posted every day )

rajulama

thanks. what can be an alternative to fileInfo?

Christian Graus

you have the path already, use System.IO.Path.GetDirectoryName and Path.GetFileName to get the pieces of the file path that you seem to need.

Christian Graus Driven to the arms of OSX by Vista. "I am new to programming world. I have been learning c# for about past four weeks. I am quite acquainted with the fundamentals of c#. Now I have to work on a project which converts given flat files to XML using the XML serialization method" - SK64 ( but the forums have stuff like this posted every day )

rajulama

sorry I didn't get it. Could you please give me an example?

Christian Graus

In the System.IO namespace: Path.GetDirectory("c:\documents\word.doc") will return c:\documents Path.GetFileName("c:\documents\word.doc") will return word.doc. The Path class is full of methods for manipulating and examining file paths

Christian Graus Driven to the arms of OSX by Vista. "I am new to programming world. I have been learning c# for about past four weeks. I am quite acquainted with the fundamentals of c#. Now I have to work on a project which converts given flat files to XML using the XML serialization method" - SK64 ( but the forums have stuff like this posted every day )

rajulama

but my file location is not fixed. I want users to select the access database file and display a table from it into datagridview.

Christian Graus

*sigh* Dim fi As New FileInfo(OpenFileDialog1.FileName) Dim sConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=;Data Source=" & fi.DirectoryName Dim objConn As New OleDbConnection(sConnectionString) Dim objDataSet As DataSet = New DataSet() objConn.Open() Dim objCmdSelect As New OleDbCommand("select * from [Joint Restraint Assignments]" & fi.Name, objConn) So, you take the filename from the openfiledialog and use the FileInfo object to extract the directory name and the filename. Instead, you can use the methods I gave you, to get those values from the filename property of the file dialog, directly. I am at a loss how you think what I have been saying takes away from your using a dynamic filename. If the filename was fixed, you'd type in the values in your code, not use methods to work them out, surely ?

Christian Graus Driven to the arms of OSX by Vista. "I am new to programming world. I have been learning c# for about past four weeks. I am quite acquainted with the fundamentals of c#. Now I have to work on a project which converts given flat files to XML using the XML serialization method" - SK64 ( but the forums have stuff like this posted every day )

rajulama

that means my no need to establish a connection. Do you mean to do something like: Dim fi As New FileInfo(OpenFileDialog1.FileName) path.GetFileName(&fi.name) Dim objCmdSelect As New OleDbCommand("select * from [Joint Restraint Assignments]" .....) ??? or, path.getfilename(openfiledialog1.filename) Dim objCmdSelect As New OleDbCommand("select * from [Joint Restraint Assignments]" .....)

rajulama

i think i got it. But I am confused about the data source to be use in oledbconnection:

Path.GetFileName(OpenFileDialog1.FileName)
Dim con As OleDbConnection = New OleDbConnection("Provider=Microsoft.jet.oledb.4.0;data source=???")

Christian Graus

Dim path as String =Path.GetFileName(OpenFileDialog1.FileName) will give you the path in a variable. Just calling GetFileName without storing the result, does nothing.

Christian Graus Driven to the arms of OSX by Vista. "I am new to programming world. I have been learning c# for about past four weeks. I am quite acquainted with the fundamentals of c#. Now I have to work on a project which converts given flat files to XML using the XML serialization method" - SK64 ( but the forums have stuff like this posted every day )

rajulama

thanks i got it. so what should be the data source in:

Dim path1 As String = Path.GetFileName(OpenFileDialog1.FileName)
Dim con As OleDbConnection = New OleDbConnection("Provider=Microsoft.jet.oledb.4.0;data source=???")

rajulama

Dim con As OleDbConnection = New OleDbConnection("Provider=Microsoft.jet.oledb.4.0;data source=" & path1 & "")

above code works. Thank you very very much

rajulama

:)

Luc Pattyn

rajulama wrote:

Dim sConnectionString As String = "..." & fi.DirectoryName

Trying to open a directory as a database? :)

Luc Pattyn [Forum Guidelines] [My Articles]

Avoiding unwanted divs (as in "articles needing approval") with the help of this FireFox add-in

Dave Kreskowiak

rajulama wrote:

Dim sConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=;Data Source=" & fi.DirectoryName

The names used in your code, you're trying to open a directory as a database. You have to give it the path to the .MDB file, not just it's parent directory.

rajulama wrote:

Dim objCmdSelect As New OleDbCommand("select * from table1" & fi.Name, objConn)

On top of that, your SQL query to get the data in table1 (if it even exists in that database) is wrong. You appending the filename to the end of the SQL SELECT statement, which won't work. The filename goes in the Data Source if your connection string, not the SELECT statement.

A guide to posting questions on CodeProject[^]
Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic
2006, 2007, 2008