Using strings in XML Literals

Question

I'm a C# developer who's fumbling in the first VB code he's written since VB6, so if I am asking a rather obvious question, please forgive me.

I decided to experiment with XML Literals to generate some XML code for me, instead of using XMLDocument

I have 2 questions, the second regarding a workaround due to my inability to figure out the first.

1: Ideal solution

I have a Dictionary of ElementName, ElementValue whose KeyValue pairs I was looping over in the hope of generating the values dynamically, but the following syntax dies a horrible death

Dim xConnections As XElement        
For Each connection As Connection In connections.AsList
    For Each kvp As KeyValuePair(Of String, String) In connection.DecompiledElements
        xConnections = <Connections> <<%= kvp.Key %>><%= kvp.Value %><\<%=kvp.Key %>>  </Connections>
    Next
Next

I have vague memories of the T4 syntax (the <%=%> syntax) being able to handle more complex operations (rather than direct assignment to the <%= ) and a 'Response.Write' like object to write output to, but I can't remember the details.

2: Cludgy workaround

Instead I thought of building a StringBuilder object and assigning its .ToString to the XElement, but that also failed with a conversion error.

I would prefer to continue using my key value pair concept in example one above, as I feel cludging together a string as in example 2 above is rather nasty, and I really should go back to using XMLDocument if instead.

Answer 1

VB.NET XML Literals are very powerful, but most often adding some LINQ to them makes them truly awesome. This code should do exactly what you're trying to do.

Dim Elements = New Dictionary(Of String, String)
Elements.Add("Key1", "Value1")
Elements.Add("Key2", "Value2")
Elements.Add("Key3", "Value3")

Dim xConnections = <Connections>
                       <%= From elem In Elements _
                           Select <<%= elem.Key %>><%= elem.Value %></> %>
                   </Connections>

The empty closing tag </> is all that is needed for the vb compiler to properly construct an xml element whose name is generated from a value within a <%= %> block.

Calling xConnections.ToString renders the following:

<Connections>
    <Key1>Value1</Key1>
    <Key2>Value2</Key2>
    <Key3>Value3</Key3>
</Connections>