I'm not new to VBA but I am new to classes and I'm struggling at the moment with initialising some dictionaries.
Here's a cut down version of my class:
Option Explicit
'Variables required for object operations
Private pFilePath As String 'contains the file path of the TAB file.
...
Private pDATAFields As Object 'dictionary1
Private pMetadata As Object 'dictionary2
Private Sub Class_Initialize()
Set pDATAFields = CreateObject("Scripting.Dictionary")
Set pMetadata = CreateObject("Scripting.Dictionary")
End Sub
...
Public Property Get DATAFields() As Object
DATAFields = pDATAFields
End Property
Public Property Get Metadata() As Object
Metadata = pMetadata
End Property
'Methods required
Public Sub initialise(sFilePath As String)
'sTABText contains the text from file at sFilePath
Dim sTabText As String
sTabText = harvestTextFile(sFilePath)
...
pTABVersion = pullPart("Version", strArr(1), 1)
...
Set pDATAFields = generateFieldStructureDict(strArr, 6, 5 + pDATAFieldNumber)
...
'Generate the metadata dictionary from the file
Set pMetadata = generateMetadataDict(strArr, i + 1)
End Sub
Private Function generateFieldStructureDict(arg1 as string, arg2 as integer, arg3 as Integer) as Object
Dim oObj as Object
Set oObj = CreateObject("scripting.dictionary")
... do stuff
Set generateFieldStructureDict = oObj
End Function
... Similar function for generateMetadataDict
From my own observations this should work but for some reason it doesn't. The properties such as pTABVersion get set fine. It just appears to be pDATAFields and pMetadata which aren't getting set properly.
If I follow the function generateFieldStructureDict step by step I see that by the end of the function when I am doing:
set generateFieldStructureDict = oObj
this part works absolutely fine. The dictionary in oObj is passed onto generateFieldStructureDict. However when we then return to the initialise sub routine:
Set pDATAFields = generateFieldStructureDict(strArr, 6, 5 + pDATAFieldNumber)
generateFieldStructureDict appears to lose all the data I gave it. Ultimately clsTab.filePath and clsTab.tabVersion will return the pFilePath and pTabVersion (because they have been set). However clsTab.DATAFields and clsTab.Metadata will not return dictionaries like they are supposed to. This is because pMetadata and pDATAFields are not set for some reason.
Does anyone have any ideas as to what I need to do to get this working?
Related
Ok to start off, I read through this.
It is close although it doesn't answer my specific question. This talks about taking smaller collections and adding items to a larger main collection. Then destroying the smaller collection.
I have two definitions under Class Modules.
TimeDet
Option Explicit
Public recDate As String
Public recQty As String
Public recDieNo As String
Public recCatID As String
Public recCatName As String
Public recGroupID As String
Public recGroupName As String
TimeRec
Option Explicit
Private objTimeRec As Collection
Private Sub Class_Initialize()
Set objTimeRec = New Collection
End Sub
Private Sub Class_Terminate()
Set objTimeRec = Nothing
End Sub
Public Property Get NewEnum() As IUnknown
Set NewEnum = objTimeRec.[_NewEnum]
End Property
Public Sub Add(obj As TimeDet)
objTimeRec.Add obj
End Sub
Public Sub Remove(Index As Variant)
objTimeRec.Remove Index
End Sub
Public Property Get Item(Index As Variant) As TimeDet
Set Item = objTimeRec.Item(Index)
End Property
Property Get Count() As Long
Count = objTimeRec.Count
End Property
Public Sub Clear()
Set objTimeRec = New Collection
End Sub
Public Sub FillFromArray(Arr As Variant)
Dim i As Long, obj As TimeDet
For i = 1 To UBound(Arr)
Set obj = New TimeDet
obj.recDate = Arr(i, 1)
obj.recQty = Arr(i, 2)
obj.recDieNo = Arr(i, 3)
obj.recCatID = Arr(i, 4)
obj.recCatName = Arr(i, 5)
obj.recGroupID = Arr(i, 6)
obj.recGroupName = Arr(i, 7)
Me.Add obj
Next
End Sub
Then in the code I am using it this way:
Sub Test()
Dim RecSet1 As TimeRec, Record As TimeDet
Dim fSet1 As TimeRec, fRecord As TimeDet
Dim repArray() As Variant
Dim startDT As Date, endDT As Date, dieNo As String
repArray() = Sheet4.Range("A2:G" & Sheet4.Range("A2").End(xlDown).Row)
Set RecSet1 = New TimeRec
Set fSet1 = New TimeRec
RecSet1.FillFromArray (repArray())
startDT = "1-1-2015"
endDT = "1-1-2016"
dieNo = "16185"
For Each Record In RecSet1
If Record.recDate <= endDT And Record.recDate >= startDT And Record.recDieNo = dieNo Then
fSet1.Add (Record)
End If
Next
End Sub
I am getting an error when I try to add the Record object to the fSet1 object.
"Object doesn't support this method or property"
The Record object is Type TimeDet which as you can see up in the class module my Add method is expecting type TimeDet.
Either I am missing something very simple and have blinders on, or this is a bigger issue.
The array has 200,000 records roughly. I am attempting to create a smaller subset of filtered data. Maybe I am approaching this from the wrong way.
Your error is not at Add but at For Each
Most likely you copied your TimeRec Class. In VBA, you can't create enumerable classes inside the VBE (VBA IDE). There's a different way of creating Enumerable classes.
Open a notepad, copy all your class code and then add this attribute to NewEnum property Attribute NewEnum.VB_UserMemId = -4
Then import the class.
This is always hidden in VBA code, but can be seen in text editors.
Also add this attribute to Item property, it will make it default and allows syntax like ClassName(1)
Attribute Item.VB_UserMemId = 0
So , your code in text editor/ notepad should be:
VERSION 1.0 CLASS
BEGIN
MultiUse = -1 'True
END
Attribute VB_Name = "Class1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Option Explicit
Private objTimeRec As Collection
Private Sub Class_Initialize()
Set objTimeRec = New Collection
End Sub
Private Sub Class_Terminate()
Set objTimeRec = Nothing
End Sub
Public Property Get NewEnum() As IUnknown
Attribute NewEnum.VB_UserMemId = -4
Set NewEnum = objTimeRec.[_NewEnum]
End Property
Public Sub Add(obj As Class2)
objTimeRec.Add obj
End Sub
Public Sub Remove(Index As Variant)
objTimeRec.Remove Index
End Sub
Public Property Get Item(Index As Variant) As Class2
Attribute Item.VB_UserMemId = 0
Set Item = objTimeRec.Item(Index)
End Property
Property Get Count() As Long
Count = objTimeRec.Count
End Property
Public Sub Clear()
Set objTimeRec = New Collection
End Sub
The answer to this particular problem was to remove the parenthesis form my Add method. That being said, the attribute info being hidden was really good info and would have probably contributed to the problem after I figured out that removing the parenthesis fixed it.
I have a dictionary in my Main Sub (KEY = string; VALUE = Class Object). The Class Object consists of two dictionaries. As I collect data and check the values stored in the Dictionary Values (Class Object - dictionaries) I noticed that only the last values are getting stored. What I mean is that all the Values in my dictionary in my Main Sub are pointing to the same dictionary reference, hence, all the instances of my Class Objects contain the same data. This means that I need to make a clone of my Class Objects (deep copy?). I have successfully done this before with Class Objects that only stored simple values, but not with dictionaries. I need help cloning my Class Object that contains dictionaries.
MAIN SUB
Dim dGroup As New Scripting.Dictionary ' Main Dictionary
'
' loop thru a listbox
For i = 0 To UserForm1.ListBox1.ListCount - 1
Gname = UserForm1.ListBox1.List(i) ' get listbox names
' populate temp dictionary
Set dic = FNC.GET_SESSION_FILE_ELEMENTS(mySesFile, Gname)
'
' instantiate new Class Object
Dim NewCol As New cVM_Col
Call NewCol.INIT(dic) ' pass the dictionary to a 'constructor'
dGroup.Add Gname, NewCol.CLONE ' add to the MAIN SUB dictionary
'
Set dic = Nothing ' clear the temp dictionary
Next i
CLASS OBJECT
Private dElms As Scripting.Dictionary
Private dDat As Scripting.Dictionary
'
Private Sub Class_Initialize()
Set dElms = New Scripting.Dictionary
Set dDat = New Scripting.Dictionary
End Sub
'
Public Sub INIT(inp As Scripting.Dictionary)
Set dElms = inp
End Sub
'
Public Function CLONE()
Set CLONE = New cVM_Col
Set CLONE.dElms = dElms ' <-- THIS IS WHERE IT CRASHES
Set CLONE.dDat = dDat
End Function
Normally my CLONE function works when I am only cloning simple data types like String or Long or Double. I've never had to do this with a Dictionary.
To CLONE the dictionary objects in my CLASS Objects I had to make the following changes:
CLASS OBJECT
(Modified CLONE function)
Public Function CLONE()
Set CLONE = New cVM_Col
CLONE.Elms = dElms
CLONE.Dat = dDat
End Function
(Added Properties)
Public Property Get Elms() As Scripting.Dictionary
Set Elms = dElms
End Property
Public Property Let Elms(p As Scripting.Dictionary)
Set dElms = p
End Property
'
Public Property Get Dat() As Scripting.Dictionary
Set Dat = dDat
End Property
Public Property Let Dat(p As Scripting.Dictionary)
Set dDat = p
End Property
In Excel 2013, I have two classes: LoadCase and LoadCombination, which implement interface ILoadCase.
The declaration for ILoadCase is:
Option Explicit
'' Public properties
Public Property Get Name() As String
End Property
Public Property Let Name(ByVal value As String)
End Property
Public Property Get ID() As Long
End Property
Public Property Let ID(ByVal valus As Long)
End Property
And the (partial) implementations for both LoadCase and LoadCombination are:
Option Explicit
Implements ILoadCase
'' Public properties
Public Property Get ILoadCase_Name() As String
ILoadCase_Name = pName
End Property
Private Property Let ILoadCase_Name(ByVal value As String)
pName = value
End Property
Public Property Get ILoadCase_ID() As Long
ILoadCase_ID = pID
End Property
Private Property Let ILoadCase_ID(ByVal value As Long)
pID = value
End Property
I've omitted code which is irrelevant to the implementation of the interface.
I then have a class BeamForces, which contains results for a particular ILoadCase object:
Option Explicit
Public Fx As Double
Public Fy As Double
Public Fz As Double
Public Mx As Double
Public My As Double
Public Mz As Double
Public ParentLoadCase As ILoadCase
I thought that with this I'd be able to do something like this:
Set currentBeamForces = New BeamForces
With currentBeamForces
.Fx = forces(0)
.Fy = forces(1)
.Fz = forces(2)
.Mx = forces(3)
.My = forces(4)
.Mz = forces(5)
Set .ParentLoadCase = TargetLoadCase
End With
Where TargetLoadCase is either a LoadCase or a LoadCombination, but this gives me an error every time.
I've coded this like I would in .NET and just expected that it would work, but does casting to an interface not work in VBA? Or am I going wrong here somewhere?
EDIT
More details. I first call the following method:
Public Function LoadBeamForcesAtNode(ByVal TargetBeam As Beam, ByVal TargetNode As Node, Optional ByVal TargetLoadCases As Collection = Nothing) As Boolean
Dim i As Integer
Dim currentLoadCase As Variant
Dim targetBeamForces As BeamForces
If TargetLoadCases Is Nothing Then
For Each currentLoadCase In Me.LoadCases.Items
Call TargetLoadCases.Add(currentLoadCase)
Next
For Each currentLoadCase In Me.LoadCombinations.Items
Call TargetLoadCases.Add(currentLoadCase)
Next
End If
'On Error GoTo ExitPoint
For Each currentLoadCase In TargetLoadCases
Set targetBeamForces = InstantiateBeamForces(TargetBeam, TargetNode, currentLoadCase)
If TargetNode Is TargetBeam.Node1 Then
Set TargetBeam.Forces1 = targetBeamForces
Else
Set TargetBeam.Forces2 = targetBeamForces
End If
Next
LoadBeamForcesAtNode = True
ExitPoint:
End Function
Where TargetLoadCases is a collection which can contain both LoadCase and LoadCombination objects.
The problem occurs in InstantiateBeamForces, the code for which is
Private Function InstantiateBeamForces(ByVal TargetBeam As Beam, ByVal TargetNode As Node, ByVal TargetLoadCase As Variant) As BeamForces
Dim forces(5) As Double
Dim currentBeamForces As BeamForces
Call Me.output.GetMemberEndForces(TargetBeam.ID, IIf(TargetNode Is TargetBeam.Node1, 0, 1), TargetLoadCase.ILoadCase_ID, forces, 0)
Set currentBeamForces = New BeamForces
With currentBeamForces
.Fx = forces(0)
.Fy = forces(1)
.Fz = forces(2)
.Mx = forces(3)
.My = forces(4)
.Mz = forces(5)
Set .ParentLoadCase = TargetLoadCase
End With
Set InstantiateBeamForces = currentBeamForces
End Function
Which creates a new BeamForces object and populates it with the values returned by the ...GetMemberEndForces(...) API COM call.
The problem is that the .ParentLoadCase property is nothing after the assignment, so I'm assuming an invalid cast...
** EDIT 2 **
Here is a screenshot of TargetLoadCase when I put a breakpoint in InstantiateBeamForces.
The ILoadCase member is Nothing, but I don't get why. Could this be the cause of the problem?
I'm trying to create a custom property in an excel sheet, then retrieve its value. This is fine when I don't use an empty string, i.e. "". When I use the empty string, I get this error:
Run-time error '7':
Out of memory
Here's the code I'm using:
Sub proptest()
Dim cprop As CustomProperty
Dim sht As Worksheet
Set sht = ThisWorkbook.Sheets("control")
sht.CustomProperties.Add "path", ""
For Each cprop In ThisWorkbook.Sheets("control").CustomProperties
If cprop.Name = "path" Then
Debug.Print cprop.Value
End If
Next
End Sub
The code fails at Debug.Print cprop.value. Shouldn't I be able to set the property to "" initially?
With vbNullChar it works, sample:
Sub proptest()
Dim sht As Worksheet
Set sht = ThisWorkbook.Sheets("control")
' On Error Resume Next
sht.CustomProperties.Item(1).Delete
' On Error GoTo 0
Dim pathValue As Variant
pathValue = vbNullChar
Dim pathCustomProperty As CustomProperty
Set pathCustomProperty = sht.CustomProperties.Add("path", pathValue)
Dim cprop As CustomProperty
For Each cprop In ThisWorkbook.Sheets("control").CustomProperties
If cprop.Name = "path" Then
Debug.Print cprop.Value
End If
Next
End Sub
I think from the comments and the answer from Daniel Dusek it is clear that this cannot be done. The property should have at least 1 character to be valid, an empty string just isnt allowed and will give an error when the .Value is called.
So you Add this property with a length 1 or more string and you Delete the property again when no actual value is to be assigned to it.
As already mentioned it is not possible to set empty strings.
An easy workaround is to use a magic word or character, such as ~Empty (or whatever seems proof enough for you):
Dim MyProperty As Excel.CustomProperty = ...
Dim PropertyValue As String = If(MyProperty.Value = "~Empty", String.Empty, MyPropertyValue)
A slightly more expensive workaround but 100% safe is to start all the values of your custom properties with a character that you then always strip off. When accessing the value, systematically remove the first character:
Dim MyProperty As Excel.CustomProperty = ...
Dim PropertyValue As String = Strings.Mid(MyProperty.Value, 2)
You can write an extension to make your life easier:
<System.Runtime.CompilerServices.Extension>
Function ValueTrim(MyProperty as Excel.CustomProperty) As String
Return Strings.Mid(MyProperty.Value, 2)
End Function
Now you can use it like this: Dim MyValue As String = MyProperty.ValueTrim
Use a reversed principle when you add a custom property:
<System.Runtime.CompilerServices.Extension>
Function AddTrim(MyProperties As Excel.CustomProperties, Name As String, Value As String) as Excel.CustomProperty
Dim ModifiedValue As String = String.Concat("~", Value) 'Use ~ or whatever character you lie / Note Strig.Concat is the least expensive way to join two strings together.
Dim NewProperty As Excel.CustomProperty = MyProperties.Add(Name, ModifiedValue)
Return NewProperty
End Function
To use like this: MyProperties.AddTrim(Name, Value)
Hope this helps other people who come across the issue..
Based on the other answers and some trial and error, I wrote a class to wrap a Worksheet.CustomProperty.
WorksheetProperty:Class
Sets and Gets the value of a Worksheet.CustomProperty and tests if a Worksheet has the CustomProperty
VERSION 1.0 CLASS
Attribute VB_Name = "WorksheetProperty"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
'#Folder("Classes")
'#PredeclaredId
Option Explicit
Private Type TMembers
Name As String
Worksheet As Worksheet
End Type
Private this As TMembers
Public Property Get Create(pWorksheet As Worksheet, pName As String) As WorksheetProperty
With New WorksheetProperty
Set .Worksheet = pWorksheet
.Name = pName
Set Create = .Self
End With
End Property
Public Property Get Self() As WorksheetProperty
Set Self = Me
End Property
Public Property Get Worksheet() As Worksheet
Set Worksheet = this.Worksheet
End Property
Public Property Set Worksheet(ByVal pValue As Worksheet)
Set this.Worksheet = pValue
End Property
Public Property Get Name() As String
Name = this.Name
End Property
Public Property Let Name(ByVal pValue As String)
this.Name = pValue
End Property
Public Property Get Value() As String
Dim P As CustomProperty
For Each P In Worksheet.CustomProperties
If P.Name = Name Then
Value = P.Value
Exit Property
End If
Next
End Property
Public Property Let Value(ByVal pValue As String)
Delete
Worksheet.CustomProperties.Add Name:=Name, Value:=pValue
End Property
Public Property Get hasCustomProperty(pWorksheet As Worksheet, pName As String) As Boolean
Dim P As CustomProperty
For Each P In pWorksheet.CustomProperties
If P.Name = pName Then
hasCustomProperty = True
Exit Property
End If
Next
End Property
Public Sub Delete()
Dim P As CustomProperty
For Each P In Worksheet.CustomProperties
If P.Name = Name Then
P.Delete
Exit For
End If
Next
End Sub
Usage
I have several properties of my custom Unit class return a WorksheetProperty. It makes it really easy to sync my database with my worksheets.
Public Function hasMeta(Ws As Worksheet) As Boolean
hasMeta = WorksheetProperty.hasCustomProperty(Ws, MetaName)
End Function
Public Property Get Id() As WorksheetProperty
Set Id = WorksheetProperty.Create(this.Worksheet, "id")
End Property
Public Property Get CourseID() As WorksheetProperty
Set CourseID = WorksheetProperty.Create(this.Worksheet, "course_id")
End Property
Public Property Get Name() As WorksheetProperty
Set Name = WorksheetProperty.Create(this.Worksheet, "unit_name")
End Property
Simple Usage
'ActiveSheet has a CustomProperty
Debug.Print WorksheetProperty.hasCustomProperty(ActiveSheet, "LastDateSynced")
'Set a CustomProperty
WorksheetProperty.Create(ActiveSheet, "LastDateSynced").Value = Now
'Retrieve a CustomProperty
Debug.Print WorksheetProperty.Create(ActiveSheet, "LastDateSynced").Value
I have created a sort function to allow a collection of instances of a custom object to be sorted based on one of the objects properties. Is it possible to extend the existing collections class in VBA? I do not believe inheritance is supported in VBA, so I am not sure how to go about this in the proper way. I could just create a new module and place the function in that module, but that doesn't seem like the best way of doing it.
Thanks for the responses. I ended up creating my own class which extends the Collections class in VBA. Below is the code if anyone is interested.
'Custom collections class is based on the Collections class, this class extendes that
'functionallity so that the sort method for a collection of objects is part of
'the class.
'One note on this class is that in order to make this work in VBA, the Attribute method has to be added
'manually. To do this, create the class, then export it out of the project. Open in a text editor and
'add this line Attribute Item.VB_UserMemId = 0 under the Item() function and this line
'Attribute NewEnum.VB_UserMemId = -4 under the NewEnum() function. Save and import back into project.
'This allows the Procedure Attribute to be recognized.
Option Explicit
Private pCollection As Collection
Private Sub Class_Initialize()
Set pCollection = New Collection
End Sub
Private Sub Class_Terminate()
Set pCollection = Nothing
End Sub
Function NewEnum() As IUnknown
Set NewEnum = pCollection.[_NewEnum]
End Function
Public Function Count() As Long
Count = pCollection.Count
End Function
Public Function item(key As Variant) As clsCustomCollection
item = pCollection(key)
End Function
'Implements a selection sort algorithm, could likely be improved, but meets the current need.
Public Sub SortByProperty(sortPropertyName As String, sortAscending As Boolean)
Dim item As Object
Dim i As Long
Dim j As Long
Dim minIndex As Long
Dim minValue As Variant
Dim testValue As Variant
Dim swapValues As Boolean
Dim sKey As String
For i = 1 To pCollection.Count - 1
Set item = pCollection(i)
minValue = CallByName(item, sortPropertyName, VbGet)
minIndex = i
For j = i + 1 To pCollection.Count
Set item = pCollection(j)
testValue = CallByName(item, sortPropertyName, VbGet)
If (sortAscending) Then
swapValues = (testValue < minValue)
Else
swapValues = (testValue > minValue)
End If
If (swapValues) Then
minValue = testValue
minIndex = j
End If
Set item = Nothing
Next j
If (minIndex <> i) Then
Set item = pCollection(minIndex)
pCollection.Remove minIndex
pCollection.Add item, , i
Set item = Nothing
End If
Set item = Nothing
Next i
End Sub
Public Sub Add(value As Variant, key As Variant)
pCollection.Add value, key
End Sub
Public Sub Remove(key As Variant)
pCollection.Remove key
End Sub
Public Sub Clear()
Set m_PrivateCollection = New Collection
End Sub
One popular option is to use an ADO disconnected recordset as a sort of hyperpowered collection/dictionary object, which has built-in support for Sort. Although you are using ADO, you don't need a database.
I would create a wrapper class that exposes the collection object's properties, substituting the sort function with your own.