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Visual Studio62
Hi,



I am getting "Name objDR is not declared" error. I am declaring objDR in

the if

then else section. How do I over come this issue.



Thanks for the help.



Dim objDS As New DataSet("Root")

Dim strXml As New StringBuilder

Dim strTable As String = "row"

Dim objRetMetaData As New DataSet

Dim blnNextResult As Boolean = True

Dim intCount As Integer = 0

Dim intIndex As Integer = 0



If OpenConnection() Then

If retType = eReturnType.eDataSet Then

If mDatabaseType = eDatabaseType.eODBC Then

Dim objCmd As New Odbc.OdbcCommand(sql,

oODBCConnection)

objCmd.CommandType = CommandType.Text



Dim objDA As New Odbc.OdbcDataAdapter(objCmd)

objDA.Fill(objDS, strTable)

mDataSetObj = objDS

Else

'Create the Command Object

Dim objCmd As New SqlClient.SqlCommand(sql,

objSQLConn)

objCmd.CommandType = CommandType.Text

Dim objDA As New SqlClient.SqlDataAdapter(objCmd)

objDA.Fill(objDS, strTable)

mDataSetObj = objDS

End If

Else

If mDatabaseType = eDatabaseType.eODBC Then

Dim objCmd As New Odbc.OdbcCommand(sql,

oODBCConnection)

objCmd.CommandType = CommandType.Text

Dim objDR As OdbcDataReader = objCmd.ExecuteReader

Else

Dim objCmd As New SqlClient.SqlCommand(sql,

objSQLConn)

objCmd.CommandType = CommandType.Text

Dim objDR As SqlDataReader = objCmd.ExecuteReader

End If

strXml.Append("<Root>")

Do Until blnNextResult = False

If objDR.HasRows() = False Then

Exit Do

Else

While objDR.Read()

strXml.Append("<row")

For intIndex = 0 To objDR.FieldCount - 1

strXml.Append(" " &

objDR.GetName(intIndex) & "=""" _

& objDR.GetValue(intIndex) & """")

Next

strXml.Append("/>")

End While



blnNextResult = objDR.NextResult()

If blnNextResult = True Then

intCount += 1

End If



End If

Loop

strXml.Append("</Root>")

mReturnXML = strXml.ToString

objDR.Close()

End If

End If


-

Move the declaration to the top (dim objDR as OdbcDataReader). Keep the

initialization where it is, (objDR = objCmd.ExecuteReader).



"Vic" wrote:

I cannot because I am declaring objDR as sqlDataReader in the else condition.



Thanks,

Vic



"Family Tree Mike" wrote:

Sorry, now I see what you are trying to do.



SqlDataReader and OdbcDataReader both inherit from DbDataReader, so that

should be the declared type at the top of your routine.



"Vic" wrote:

On 2008-04-07, Vic <Vic@discussions.microsoft.com>wrote:

Your main problem is that you are trying to reuse the same names for

different types, and you are expecting a value declared in on block to

be visible in another... The simplest fix for this method is to move

your Command and DataReader declarations out of the if blocks to the top

of your method. You'll want to declare them as IDbCommand and

IDataReader...



Dim objCmd As IDbCommand

Dim objDR As IDataReader





This means that you will remove the declaration syntax at their

initialization and it will look like:



objCmd = New Odbc.OdbcCommand(Sql, oODBCConnnection)



Same with the reader. This will mean that you will have to remove the

call to objDR.HasRows - since that is not defined on IDataReader

inteface, but I really don't see it necessary on the code you have

written.



There are a lot of other refactorings that I would consider as well.

For example, you could simply have your OpenConnection method return a

IDBConnection. Basically, I would create factories for your various db

objects that create the correct types, but return them as the generic

interfaces that all of these types implement. Write to the interface,

not to the implementation. In the rare case that you might need an

implementation specific method/property, you can always do a trycast or

an is test:



dim sqlconnection = trycast(connection, sqlconnection)

if not sqlconnection is nothing then

' call sqlconnection specific method

end if



HTH

--

Tom Shelton

-