VBA有字典结构吗?比如key<>value array?
当前回答
是的。适用于VB6, VBA (Excel), VB。网
其他回答
如果由于任何原因,您不能或不想在Excel中安装额外的功能,您也可以使用数组,至少对于简单的问题。 你输入这个国家的名字,函数就会返回它的资本。
Sub arrays()
Dim WhatIsCapital As String, Country As Array, Capital As Array, Answer As String
WhatIsCapital = "Sweden"
Country = Array("UK", "Sweden", "Germany", "France")
Capital = Array("London", "Stockholm", "Berlin", "Paris")
For i = 0 To 10
If WhatIsCapital = Country(i) Then Answer = Capital(i)
Next i
Debug.Print Answer
End Sub
是的。适用于VB6, VBA (Excel), VB。网
所有其他人都已经提到了Dictionary类的scripting.runtime版本的使用。如果您无法使用此DLL,您也可以使用此版本,只需将其添加到代码中。
https://github.com/VBA-tools/VBA-Dictionary/blob/master/Dictionary.cls
它与微软的版本完全相同。
基于cjrh的答案,我们可以构建一个不需要标签的Contains函数(我不喜欢使用标签)。
Public Function Contains(Col As Collection, Key As String) As Boolean
Contains = True
On Error Resume Next
err.Clear
Col (Key)
If err.Number <> 0 Then
Contains = False
err.Clear
End If
On Error GoTo 0
End Function
在我的一个项目中,我编写了一组帮助函数,使集合的行为更像字典。它仍然允许递归收集。你会注意到Key总是排在前面,因为它是强制性的,在我的实现中更有意义。我也只使用字符串键。如果你愿意,你可以改回来。
Set
我将其重命名为set,因为它将覆盖旧值。
Private Sub cSet(ByRef Col As Collection, Key As String, Item As Variant)
If (cHas(Col, Key)) Then Col.Remove Key
Col.Add Array(Key, Item), Key
End Sub
Get
err的东西是为对象,因为你会传递对象使用set和变量没有。我觉得你可以检查一下它是不是一个物体,但我时间很紧。
Private Function cGet(ByRef Col As Collection, Key As String) As Variant
If Not cHas(Col, Key) Then Exit Function
On Error Resume Next
err.Clear
Set cGet = Col(Key)(1)
If err.Number = 13 Then
err.Clear
cGet = Col(Key)(1)
End If
On Error GoTo 0
If err.Number <> 0 Then Call err.raise(err.Number, err.Source, err.Description, err.HelpFile, err.HelpContext)
End Function
Has
写这篇文章的原因是…
Public Function cHas(Col As Collection, Key As String) As Boolean
cHas = True
On Error Resume Next
err.Clear
Col (Key)
If err.Number <> 0 Then
cHas = False
err.Clear
End If
On Error GoTo 0
End Function
删除
如果它不存在就不抛出。只要确保它被移除。
Private Sub cRemove(ByRef Col As Collection, Key As String)
If cHas(Col, Key) Then Col.Remove Key
End Sub
Keys
获取一个键数组。
Private Function cKeys(ByRef Col As Collection) As String()
Dim Initialized As Boolean
Dim Keys() As String
For Each Item In Col
If Not Initialized Then
ReDim Preserve Keys(0)
Keys(UBound(Keys)) = Item(0)
Initialized = True
Else
ReDim Preserve Keys(UBound(Keys) + 1)
Keys(UBound(Keys)) = Item(0)
End If
Next Item
cKeys = Keys
End Function
VBA有收集对象:
Dim c As Collection
Set c = New Collection
c.Add "Data1", "Key1"
c.Add "Data2", "Key2"
c.Add "Data3", "Key3"
'Insert data via key into cell A1
Range("A1").Value = c.Item("Key2")
Collection对象使用散列执行基于键的查找,因此速度很快。
你可以使用Contains()函数来检查一个特定的集合是否包含键:
Public Function Contains(col As Collection, key As Variant) As Boolean
On Error Resume Next
col(key) ' Just try it. If it fails, Err.Number will be nonzero.
Contains = (Err.Number = 0)
Err.Clear
End Function
编辑2015年6月24日:短包含()感谢@TWiStErRob。
2015年9月25日编辑:感谢@scipilot,添加了Err.Clear()。