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copied!<p>I have a database file that I beleive was created with Clipper but can't say for sure (I have .ntx files for indexes which I understand is what Clipper uses). I am trying to create a C# application that will read this database using the System.Data.OleDB namespace.</p> <p>For the most part I can sucessfully read the contents of the tables there is one field that I cannot. This field called CTRLNUMS that is defined as a CHAR(750). I have read various articles found through Google searches that suggest field larger than 255 chars have to be read through a different process than the normal assignment to a string variable. So far I have not been successful in an approach that I have found.</p> <p>The following is a sample code snippet I am using to read the table and includes two options I used to read the CTRLNUMS field. Both options resulted in 238 characters being returned even though there is 750 characters stored in the field.</p> <p>Here is my connection string:</p> <p>Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\datadir;Extended Properties=DBASE IV;</p> <p>Can anyone tell me the secret to reading larger fields from a DBF file?</p> <pre><code>using (OleDbConnection conn = new OleDbConnection(connectionString)) { conn.Open(); using (OleDbCommand cmd = new OleDbCommand()) { cmd.Connection = conn; cmd.CommandType = CommandType.Text; cmd.CommandText = string.Format("SELECT ITEM,CTRLNUMS FROM STUFF WHERE ITEM = '{0}'", stuffId); using (OleDbDataReader dr = cmd.ExecuteReader()) { if (dr.Read()) { stuff.StuffId = dr["ITEM"].ToString(); // OPTION 1 string ctrlNums = dr["CTRLNUMS"].ToString(); // OPTION 2 char[] buffer = new char[750]; int index = 0; int readSize = 5; while (index < 750) { long charsRead = dr.GetChars(dr.GetOrdinal("CTRLNUMS"), index, buffer, index, readSize); index += (int)charsRead; if (charsRead < readSize) { break; } } } } } } </code></pre>

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