Using Strings to Call objects

rpjamess1 · May 30th, 2007, 11:33 AM

I'm trying to cut down on processing time by creating a method that uses string to create object calls. For example:

I have an XML file with several fields. I am trying to populate a ListView using the data from the XML file. Normally, I would call the characterData object that contains the XML data. My code would look like:

Code:

Dim characterData As New CharacterData

Dim listItem As New ListViewItem
        Dim skill(3) As String

        skill(0) = "Appraise"
        skill(1) = objRPG.SetTotal(txtInt1.Text, characterData.AppraiseMisc, characterData.AppraiseRanks).ToString
        If characterData.AppraiseCheck = True Then
            skill(2) = "Yes"
        Else
            skill(2) = "No"
        End If
        listItem = New ListViewItem(skill)
        lstSkills.Items.Add(listItem)

        skill(0) = "Astrogate"
        skill(1) = objRPG.SetTotal(txtInt1.Text, characterData.AstrogateMisc, characterData.AstrogateRanks).ToString
        If characterData.AstrogateCheck = True Then
            skill(2) = "Yes"
        Else
            skill(2) = "No"
        End If
        listItem = New ListViewItem(skill)
        lstSkills.Items.Add(listItem)

This works. The Ranks and Misc portions are simple number strings. The Check is either True or False.

I'm trying to create a method that will allow me to enter certain names and get the correct portions of the CharacterData object called.

For example:

Code:

AddItem("Appraise", "Int")

Private Sub AddItem(ByVal skillName As String, ByVal attributeName As String)

        Dim ranks As Object = "characterData." & skillName & "Ranks"
        Dim misc As Object = "characterData." & skillName & "Misc"
        Dim attribute As String = "txt" & attributeName & "1.Text"
        Dim check As Object = "characterData." & skillName & "Check"

        Dim listItem As New ListViewItem
        Dim skill(3) As String

        skill(0) = skillName
        skill(1) = objRPG.SetTotal(attribute, misc, ranks).ToString
        If check = True Then
            skill(2) = "Yes"
        Else
            skill(2) = "No"
        End If
        listItem = New ListViewItem(skill)
        lstSkills.Items.Add(listItem)

End Sub

Here, I get a return that characterData.AppraiseCheck is a string and can't be converted to a Boolean. How can I pass a string paramter and have it added to an object call? Hopefully I've explained myself clearly enough.

Thanks in advance.

BrianWren · June 1st, 2007, 10:48 AM

I don't think you'll be able to do this. The object needs to be able to be resolved before running the statement that instantiates it (as I understand it), and that isn't possible in your case.

You can call routines by name, but to do so you need to use a built-in function which is made just for that purpose. There is no equivalent function for object resolution by name.

I presume that the presence in code of the function to call procedures by name cause the compiler to store within the app the actual names of every possible candidate for such a call so as to be able to accomodate the call.

rpjamess1 · June 1st, 2007, 11:43 AM

I found a work around that requires only 1 extra line of code per method call. It doesn't call the objects within the method, but still passes parameters to streamline what I'm trying to do. Thanks for your reply.