Getting CommandLineArgs StartsWith Failing - vb.net

Question

I've got an application. I haven't had to use command line arguments before but my research suggests my method isn't wrong. In VS2015, in my project properties->debug I've added /boxID=123 but when I debug, I get nothing in my inputVal variable. Where am I going wrong?
Imports Word = Microsoft.Office.Interop.Word 'needed for COM object interaction with MS Word
Imports System.Data.SqlClient 'needed for DB interactions
Imports System.IO 'needed for BLOB
Public Class Window
'set form level declarations
Dim appPath As String
Dim objWordApp As New Word.Application
Dim objDoc As Word.Document
Function boxIDfromCommandLine() As Integer
Dim inputArg As String = "/boxID="
Dim inputVal As String = ""
For Each s As String In My.Application.CommandLineArgs
If s.ToLower.StartsWith(inputArg) Then
inputVal = s.Remove(0, inputArg.Length)
End If
Next
If inputVal = "" Then
inputVal = "0"
End If
boxIDfromCommandLine = Convert.ToInt32(inputVal)
End Function
'form load subroutine
Private Sub Window_Load(ByVal sender As System.Object, e As System.EventArgs) Handles MyBase.Load
'Establish application path, replace appPath on deployment
Dim appPath As String = Application.StartupPath()
'Run application in foreground or background.
'If in background (false), be sure to add objDoc.close() and objWordApp.Quit()
objWordApp.Visible = False
'Declarations
Dim localDateTimeString As String = DateTime.Now.ToString
Dim localDateTimeFileName As String = DateTime.Now.ToString("yyyyMMddhhmm")
Dim soNumber As String = "No_SO_Selected"
Dim boxID As Integer = boxIDfromCommandLine()
Dim saveString As String 'file name format
Dim savePath As String = "C:\ITO_PackingLists" 'set folder location
Dim connection As SqlConnection = New SqlConnection() 'set SQL server connection string
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