Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
menu search
person
Welcome To Ask or Share your Answers For Others

Categories

Below it the code I'm using to connect to an Access database and pull the values from the query. Problem is.. I cannot get any values back from the reader object. I can see that there are the correct amount of rows, however I keep getting an InvalidOperationException (whether I use GetValue() or GetString()) saying "No data exists for the row/column."

        System.Data.OleDb.OleDbConnection conn = new
        System.Data.OleDb.OleDbConnection();
        conn.ConnectionString = @"Provider=Microsoft Office 12.0 Access Database Engine OLE DB Provider;" +
                                @"Data source= C:Users
earodDesktopImportDB.accdb";
        try
        {
            conn.Open();
            OleDbCommand cmd = new OleDbCommand("SELECT * FROM [SQL Agent Unique ID Test Load]", conn);

            OleDbDataReader reader = cmd.ExecuteReader();

            string companyCode = reader.GetValue(0).ToString();
            string agentId = reader.GetString(1);
            string firstName = reader.GetString(2);
            string lastName = reader.GetString(3);
            string nameSuffix = reader.GetString(4);
            string corporateName = reader.GetString(5);
            string entityType = reader.GetString(6);
            string obfSSN = reader.GetString(7);
            string obfFEIN = reader.GetString(8);
            string dummyIndicator = reader.GetString(9);
            // Insert code to process data.
        }
        catch (Exception ex)
        {
            MessageBox.Show("Failed to connect to data source");
        }
        finally
        {
            conn.Close();
        }
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
459 views
Welcome To Ask or Share your Answers For Others

1 Answer

you have to call Read method like below (use using instead of disposing yourself connection

string connectionString = @"Provider=Microsoft Office 12.0 Access Database Engine OLE DB Provider;" + @"Data source= C:Users
earodDesktopImportDB.accdb";

string queryString=  "SELECT * FROM [SQL Agent Unique ID Test Load]";
 try
     {
    using (OleDbConnection connection = new OleDbConnection(connectionString))
        {
            OleDbCommand command = new OleDbCommand(queryString, connection);
            connection.Open();
            OleDbDataReader reader = command.ExecuteReader();

            while (reader.Read())
            {
                string companyCode = reader.GetValue(0).ToString();
            string agentId = reader.GetString(1);
            string firstName = reader.GetString(2);
            string lastName = reader.GetString(3);
            string nameSuffix = reader.GetString(4);
            string corporateName = reader.GetString(5);
            string entityType = reader.GetString(6);
            string obfSSN = reader.GetString(7);
            string obfFEIN = reader.GetString(8);
            string dummyIndicator = reader.GetString(9);
            // Insert code to process data.
            }
            reader.Close();
        }
   }
catch (Exception ex)
   {
            MessageBox.Show("Failed to connect to data source");
   }

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
...