使用listbox multiselect从列表返回多个索引时出错

Posted 2021-04-18

VBA的新手，有点沮丧。试图为我的老师们制作一份表格来简化文书工作。

我有一个表格1. apple 橙色 葡萄

如果用户要从列表中选择apple和grape，我希望单元格只包含索引。所以在单元格中打印（1,3）。我不想要这些话。

我目前的代码

Private Sub SpedAccomAddBtn_Click()

'variable to count multiple selections'
VarSped = " "

'loop to keep track of indexes of selected items'
For X = 0 To Me.SpedListBx.ListCount - 1 'count through list
    If Me.SpedListBx.Selected(X) Then    
        If VarSped = " " Then  'if blank then record first item'
            VarSped = Me.SpedListBx.ListIndex + 1 'first selected item. +1 because excel is a 0 based index'
        Else 'if not the first selection add a , between selections'
            VarSped = VarSped & "," & Me.SpedListBx.ListIndex + 1
        End If
    End If
Next X

ThisWorkbook.Sheets("Master SPED Sheet").Range("c4") = VarSped 'print to cell'

如果我使用前面选择Apple和Grape的例子，我得到（3,3）不是（1,3）。我无法弄清楚为什么VarSped会被覆盖。 （我是编码的新手，我必须评论一切，所以我觉得我知道我在做什么）

答案

你的循环迭代器已经是你的项目位置：只需添加一个来管理基于0的列表：

Option Explicit

Private Sub SpedAccomAddBtn_Click()
    Dim VarSped As String ' a string is always initialized with a null string, i.e. with a "" string. hence no need for a 'VarSped = ""' statement

    Dim X As Long
    For X = 0 To Me.SpedListBx.ListCount - 1 'count through list
        If Me.SpedListBx.Selected(X) Then VarSped = VarSped & "," & X + 1
    Next

    If VarSped <> vbNullString Then ThisWorkbook.Sheets("Master SPED Sheet").Range("c4") = Mid$(VarSped, 2) ' print 'VarSped' only if user selected something (i.e. 'VarSped' is not a not string). Mid$() function is used to skip the first character which is a colon 
End Sub

养成将Option Explicit放在每个模块的topo中并明确声明所有变量的习惯：这样既可以节省大量的调试时间，又可以让你对代码有更多的控制权

另一答案

试试这个，看看如何引用循环中的当前项：

Private Sub SpedAccomAddBtn_Click()

Dim VarSped As String
Dim x As Integer

'variable to count multiple selections'
VarSped = " "

'loop to keep track of indexes of selected items'
For x = 0 To Me.SpedListBx.ListCount - 1 'count through list
    If Me.SpedListBx.Selected(x) Then
        If VarSped = " " Then  'if blank then record first item'
            VarSped = Me.SpedListBx.List(x) 'first selected item. +1 because excel is a 0 based index'
        Else 'if not the first selection add a , between selections'
            VarSped = VarSped & "," & Me.SpedListBx.List(x)
        End If
    End If
Next x

ThisWorkbook.Sheets("Master SPED Sheet").Range("c4") = VarSped 'print to cell'

End Sub