Question

I have a subroutine that adds an item to a Collection only if that item is not present. This effectively treats Collections as if they are sets. But VBA returns error 424 when the subroutine is called.

Private Sub SetUnion(ByVal e As String, ByVal Coll As Collection)
found = False
For n = 1 To Coll.Count
    If Coll(n) = e Then
        found = True
        Exit For
    End If
Next n
If found = False Then Coll.Add e
End Sub

当我打电话给我时

Dim s1, C  As Collection
For n = 1 To s1.Count
SetUnion s1(n), C   #
Next n

我

Run-time error ‘424’:
Object required

我做了哪些错误?

Answer 1

@braX评论说,您在《家庭、社会、文化权利国际公约》法典中使用了另一种方案拟定语言的辛加语。
根据你的法典,你似乎再次试图从扼杀中摘取独特的特性。

Option Explicit

Sub SetUnion(ByVal e As String, ByRef Coll As Collection)
    Dim n As Long
    If Not Coll Is Nothing Then
        For n = 1 To Coll.Count
            If Coll(n) = e Then
                Exit Sub
            End If
        Next n
    End If
    Coll.Add e
End Sub

Sub test()
    Dim sStr As String, oCol  As Collection, n As Long
    sStr = "abcabd"
    Set oCol = New Collection
    For n = 1 To Len(sStr)
        SetUnion Mid(sStr, n, 1), oCol
    Next n
    For n = 1 To oCol.Count
        Debug.Print oCol(n)
    Next
End Sub

产出:

a
b
c
d

Use less code lines with Dictionary object

Sub test2()
    Dim sStr As String, vKey
    Dim objDic As Object, n As Long
    Set objDic = CreateObject("scripting.dictionary")
    sStr = "abcabd"
    For n = 1 To Len(sStr)
        objDic(Mid(sStr, n, 1)) = ""
    Next n
    For Each vKey In objDic
        Debug.Print vKey
    Next
End Sub

友情链接