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Reading dBase 3 and dBase 4 files with nonstandard extensions in C#

Posted on 2008-10-09
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Last Modified: 2013-12-17
Hi. I have been using the FoxPro ODBC driver to open dBase3 files with nonstandard extensions and it works just fine. However, when I try to open a dBaseIV file I get the error "ERROR [42S02] [Microsoft][ODBC Visual FoxPro Driver]Not a table."

I have tried FoxPro OleDB driver, but apparently the files have to be named with a ".dbc" extension.

Is there anyway I can use a single driver to open these dBase 3 and dBase 4 files that have nonstandard extensions?

Below is the code I am using. And I have attached one of the files I am having issues with if anyone wants to see if they can open and read it. I had to change the extension to .txt to get it to upload, but you can change it to .veh or whatever you like.

Thanks.
string tagNum = "";
            OdbcConnection oConnection = new OdbcConnection("Driver={Microsoft Visual FoxPro Driver};SourceType=DBF;SourceDB=C:\\Documents and Settings\\Lee\\Desktop\\Mitchell EMS;Exclusive=No; Collate=Machine;NULL=NO;DELETED=NO;BACKGROUNDFETCH=NO;");
            oConnection.Open();
 
 
            OdbcDataAdapter oDataAdapter = new OdbcDataAdapter("SELECT * FROM 123A.ad1", oConnection);
            DataSet oDataSet = new DataSet();
            oDataAdapter.Fill(oDataSet);//I get the error right here...
            DataTable oDataTable = oDataSet.Tables[0];
            foreach (DataRow dr in oDataTable.Rows)
            {
 
 
                tagNum = (dr["PLATE_NO"].ToString().Trim());
              
 
            }//end foreach

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dBaseFile.zip
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Question by:TongueNGroove
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10 Comments
 

Author Comment

by:TongueNGroove
ID: 22683685
If I try to open the file using oleDB from fox pro i get the error "File must be opened exclusively to convert the Memo file."
string tagNum = "";
            OleDbConnection oConnection = new OleDbConnection("Provider=vfpoledb.1;Data Source=C:\\Documents and Settings\\Lee\\Desktop\\Mitchell EMS\\;Exclusive=Yes;Collating Sequence=machine;");
            oConnection.Open();
 
 
            OleDbDataAdapter oDataAdapter = new OleDbDataAdapter("SELECT * FROM 123A.ad1", oConnection);
            DataSet oDataSet = new DataSet();
            oDataAdapter.Fill(oDataSet);//I get the error right here...
            DataTable oDataTable = oDataSet.Tables[0];
            foreach (DataRow dr in oDataTable.Rows)
            {
 
 
                tagNum = (dr["PLATE_NO"].ToString().Trim());
              
 
            }//end foreach

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0
 
LVL 6

Expert Comment

by:carlsiy
ID: 22683786
try changing the connection string

I am using this to open dbase III and dbase IV files in c#

Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\folder;Extended Properties=dBASE IV;User ID=Admin;Password=;
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Author Comment

by:TongueNGroove
ID: 22683970
The problem with that is, the files have to have a standard .dbf extension. The files I am using have different extensions.
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Expert Comment

by:ElrondCT
ID: 22689621
So why not just rename the file before opening, then rename back when you're done?
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Author Comment

by:TongueNGroove
ID: 22690552
I can't rename the files because other systems may be accessing them at the same time and that would cause a lot of issues.

What I need is a driver and connection string that allows me to open dBase3 and dBase4 files with nonstandard extensions.

I have a program called dbase viewer that will open all of these files in a GUI, so I know it's possible. But  I have no idea how the program is doing it.
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LVL 20

Accepted Solution

by:
ElrondCT earned 500 total points
ID: 22690780
A specialized application like dBase Viewer may well be doing direct data access on a byte-by-byte basis, rather than using a standard driver. The dBase data structure is published, and is really pretty simple, so it's not an overly difficult project to do (particularly if you don't have memo files that you have to read). Obviously, not as easy as using a standard driver, but I don't know how much flexibility you'll find with them.

I found code to do that at CodeProject: http://www.codeproject.com/KB/bugs/LoadDBF.aspx. I can't vouch for it, but it looks like it might meet your needs. The author specifically mentions that it's useful for those for whom the standard Jet and FoxPro drivers aren't workable.
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Author Comment

by:TongueNGroove
ID: 22692462
Thanks for link. It does look interesting, but a bit too complex and unwieldy and I am not even sure it would be worth the trouble to try to figure out since it may not work correctly anyway.
0
 
LVL 20

Expert Comment

by:ElrondCT
ID: 22692589
You know what complexity you can handle, but I think you're overly pessimistic about the quality of what's offered; I've generally had very good results with stuff from Code Project, and as I said, the dBase file structure isn't overly difficult to process; it was designed in the early days of computing, when computers didn't have as much horsepower and developers weren't tempted to put as many bells and whistles into their systems. The article has been well rated by people using it. Note that there's a download of the actual class file; you're not expected to cut and paste from the web page.
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