VERY basic one..

Ok, I am trying to perform what I believe to be an extremely simple task and am having difficulty. I am attempting to connect to an SQL database and retrieve a first name and last name based on a customer ID. I know the SQL is good as I can run it in query analyzer and it works fine. I can successfully open a connection to the DB in my application but can not figure out how to get the information from the database via the SQLDataReader (or any other method for that matter) conn.Open(); MessageBox.Show("Connection Opened!!"); SqlCommand cmd = new SqlCommand("SELECT RTRIM (C536870914) + ' ' + RTRIM(C536870913) NAME, C536870980 PHONELOOKUP FROM ARSYSTEM.DBO.T55 WHERE C536870980 = " + txtCustID.Text, conn); reader = cmd.ExecuteReader(); string custName = reader[0].ToString(); txtCustName.Text = custName; When I run this application and attempt execute the above method I receive the following error. An unhandled exception of type 'System.InvalidOperationException' occurred in system.data.dll Additional information: Invalid attempt to read when no data is present. I'm not sure why it says no data is present as when I run this query elsewhere it does return data. Any thoughts? Thanks, Bob

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yasser_822721y ago
That's happening because you're trying to read data before calling the Read() method of SqlDataReader. Check this out on how to read data from SqlDataReader: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdatasqlclientsqldatareaderclasstopic.asp and if your query is returning only one value, then it's better to use ExecuteScalar() instead of ExecuteReader(). Check it out here on how to do this: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdatasqlclientsqldatareaderclasstopic.asp Cheers, Yasser
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