Microsoft Enterprise Library Data Access Application Blocks Execute Reader (Object must implement IConvertible)

I’ve been trying to get the MS Enterprise Library Data Access Applications Blocks working this morning. Yesterday I got the library set up and running. I started to implement the DAAB so that I could call a stored procedure, passing in a parameter, and retrieving a DataReader that I could fill into a class. But I was having some horrible problems trying to get the stored procedure to run and fill the DataReader using the DAAB.

I was continually getting the error:

“Object must implement IConvertible”

and was unable to figure out why this was.

sqlCommand = "spCMS_CustomerLostPasswordEmailAddress";

// Parameters
SqlParameter[] parms = {
    new SqlParameter("@EmailAddress", SqlDbType.VarChar, 50)
};
parms[0].Value = identifier;

DBCommandWrapper dbcw = db.GetStoredProcCommandWrapper(sqlCommand, parms);
SqlDataReader dr = db.ExecuteReader(dbcw);

It would return the error while trying to perform the ExecuteReader command.

Solution

In order to get the code to successfully function, I had to do the following:

DBCommandWrapper dbcw = db.GetStoredProcCommandWrapper("spCMS_CustomerLostPasswordEmailAddress");
dbcw.AddInParameter("@EmailAddress", DbType.String, identifier);
SqlDataReader dr = (SqlDataReader)db.ExecuteReader(dbcw);

So if you’re looking to use ExecuteReader with the Microsoft Enterprise Library Data Access Application Blocks, I hope the above code helps!

Resources I used to figure all of this out:

• Enterprise Library / Data Access Application Block Follow-up
• An Introduction to the Microsoft Enterprise Library by Scott Mitchell