Question

我已经定义了一个存储需求信息的类。它包含一个唯一的req-key。

    Option Explicit

    Private pKey As String
    Private pName As String
    Private pReqRef As New clsReqCollection
    Private pReqType As RequirementType
    Private pProblem As String

    Public Enum RequirementType
       Ziel = 0
       Fachanforderung = 1
       Produktanforderung = 2
       Prozessanforderung = 3
       Organisationsanforderung = 4
       ITAnforderung = 5
       Datenanforderung = 6
       RandUndRahmenbedingung = 7
    End Enum
    ''''''''''''''''''''''
    ' Key property
    ''''''''''''''''''''''
    Public Property Get Key() As String
        Key = pKey
    End Property
    Public Property Let Key(Value As String)
        pKey = Value
    End Property
    ''''''''''''''''''''''
    ' Name property
    ''''''''''''''''''''''
    Public Property Get Name() As String
        Name = pName
    End Property
    Public Property Let Name(Value As String)
        pName = Value
    End Property
    ''''''''''''''''''''''
    ' ReqRef property
    ''''''''''''''''''''''
    Public Property Get ReqRef() As clsReqCollection
        ReqRef = pReqRef
    End Property
    ''''''''''''''''''''''
    ' ReqType property
    ''''''''''''''''''''''
    Public Property Get ReqType() As RequirementType
       ReqType = pReqType
    End Property
    Public Property Let ReqType(Value As RequirementType)
        pReqType = Value
    End Property
    ''''''''''''''''''''''
    ' Problem property
    ''''''''''''''''''''''
    Public Property Get Problem() As String
        Problem = pProblem
    End Property
    Public Property Let Problem(Value As String)
        pProblem = Value
    End Property

现在我构建一个自定义集合来存储需求对象，如下所示

VERSION 1.0 CLASS
BEGIN
  MultiUse = -1  'True
END
Attribute VB_Name = "clsReqCollection"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Option Explicit

Private requirements As Collection

Private Sub Class_Initialize()
   Set requirements = New Collection
End Sub
Private Sub Class_Terminate()
   Set requirements = Nothing   
End Sub

Public Function NewEnum() As IUnknown
Attribute NewEnum.VB_UserMemId = -4
Attribute NewEnum.VB_MemberFlags = "40"
    Set NewEnum = requirements.[_NewEnum]
End Function

Public Sub Add(aRequirement As clsRequirement)
   requirements.Add aRequirement, aRequirement.Key
End Sub

Public Sub Remove(cIndex As Variant)
   requirements.Remove cIndex
End Sub

Public Property Get Item(cIndex As Variant) As clsRequirement
   Attribute Item.VB_UserMemId = 0
   Set Item = requirements.Item(cIndex)
End Property

Public Property Get Count() As Integer
   Count = requirements.Count
End Property

Public Sub Clear()
   Set requirements = New Collection
End Sub

当我使用对象存储密钥添加objekts时，我希望能够通过提供密钥来访问自定义集合：

Dim reqs As New clsReqCollection
Dim currReq As clsRequirement

Set currReq = New clsRequirement
currReq.Key = "Key"
currReq.Name = "Name"

reqs.Add currReq
Debug.Print reqs.Item("Key").Name

不知怎的，最后一行不起作用，我得到一个运行时错误'5'。知道这里出了什么问题吗？

Answer 1

像这样：

Dim reqs As New clsReqCollection
Dim currReq As clsRequirement

Set currReq = New clsRequirement
currReq.Key = "Key"
currReq.Name = "Name"

reqs.Add currReq, "Key"

Debug.Print reqs.Item("Key").Name

请参阅reference：

不考虑用户定义的.Key，这只是您班级的普通成员。只有内部集合键可以用作哈希表，如获取项目的键。

按键访问自定义收集项

1 个答案: