VB.NET•Translate Late-Bound VBScript to Early-Bound

Listing 1. Most VBScript event handlers, functions, and procedures build and run with Option Strict Off. The testFunctionVBScript code comes from a Microsoft.Public.InfoPath newsgroup example for calculating a running sum to display in an expression box. The code only requires one modification (Dim i) to build and run the VBScript. The testFunction upgrade to the VBScript code includes the type casts required to early-bind the objects and permit turning Option Strict On after removing the VBScript.

Function testFunctionVBScript(ByVal objNodeSet)
     'Imported VBScript code from InfoPath 
     'newsgroup. The extra parentheses are JScript 
     'detritus not required for VBScript or VBA
     Dim runningSum
     Dim i     'Added for Option Explicit On
     runningSum = 0
     If (Not (objNodeSet Is Nothing)) Then
          For i = 0 To (objNodeSet.length - 1)
               Dim objNode
               objNode = objNodeSet.nextNode
               Dim objsampleAttr
               objsampleAttr = _
                    objNode.selectSingleNode _
                    ("@my:sampleAttr")
               Dim objsampleElement
               objsampleElement = _
                    objNode.selectSingleNode _
                    ("my:sampleElement")
               If ((Not (objsampleAttr Is _
                    Nothing)) And (Not _
                    (objsampleElement Is _
                    Nothing))) Then
                    If ((IsNumeric _
                         (objsampleAttr.text)) And _
                         (IsNumeric _
                         (objsampleElement.text))) Then
                         runningSum = runningSum + _
                              objsampleAttr.text + _
                              objsampleElement.text
                    End If
               End If
          Next
     End If
     testFunctionVBSCript = runningSum
End Function

Public Function testFunction(ByVal objNodeSet _
     As IXMLDOMNodeList) As Double
     'Port of VBScript to Visual Basic .NET
     Dim intSum As Double = 0
     Dim intCtr As Integer
     Try
          If Not objNodeSet Is Nothing Then
               For intCtr = 0 To objNodeSet.length - 1
                    Dim objNode As IXMLDOMNode = _
                         objNodeSet.nextNode()
                    Dim objsampleAttr As IXMLDOMNode = _
                         objNode.selectSingleNode _
                         ("@my:sampleAttr")
                    Dim objsampleElement As _
                         IXMLDOMNode = _
                         bjNode.selectSingleNode _
                         ("my:sampleElement")
                    If Not (objsampleAttr Is Nothing) _
                         And Not (objsampleElement Is _
                         Nothing) Then
                    If IsNumeric(objsampleAttr.text) _
                         And IsNumeric _
                         (objsampleElement.text) Then
                              intSum = intSum + _
                                   CType _
                                   (objsampleAttr.text, _
                                   Double) + _
                                   CType(objsampleElement. _
                                   text, Double)
                         End If
                    End If
               Next
          End If
          Return intSum
     Catch excSum As Exception
          thisXDocument.UI.Alert(excSum.Message + _
               excSum.StackTrace)
     End Try
End Function