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POClosing Database Connections in .NET
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copied!<p>I've got the following bit of code (that another developer wrote) that I need to modify because the ExecuteProc procedure fails. (The reason why it fails isn't in the scope of this question. It's a long story) but in scope is that I'm not sure why a <code>NullReferenceException</code> would occur. It's in VB.NET (I'm not a VB.NET guy myself, so I'm not sure if this is something that is unique to VB.NET):</p> <pre><code>Imports System.Data Imports System.Data.SqlClient Imports System.Data.SqlTypes Imports System.Collections '(...) Public Overloads Function ExecuteProc( ByVal pvsProcName as String) As DataSet Dim oCommand As SqlCommand Dim oDataAdaptor As SqlDataAdapter = New SqlDataAdapter 'Other Stuff here Try oCommand = CommandGet(ConnectionGet) 'Do some more stuff that's irrelevant Catch oException As Exception Throw oException Finally ConnectionClose(oCommand.Connection) oCommand.Dispose() oDataAdaptor.Dispose() End Try End Function </code></pre> <p>I get the following warning:</p> <pre><code>Variable 'oCommand' is used before it has been assigned a value. A null reference exception could result at runtime.` </code></pre> <p><strong>Edit</strong>: I found the answer right before I posted the question. I posted it to keep it around (I hate putting ten minutes into something to dump it willy nilly).</p> <p>My subsequent question for VB.NET folks is this:</p> <p>What would be the difference in the following two intializations:</p> <pre><code>Dim oCommand As SqlCommand = Nothing </code></pre> <p>And:</p> <pre><code>Dim oCommand as New SqlComand </code></pre>

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