i use a function like below for Multi-select listboxes.
Code:
Public Function getLBX(LBx As ListBox, Optional colmn As Integer = 0, Optional delim As String = "", Optional Trm As Integer = 1) As String
'arguements:
'LBx = Name of your listbox
'colmn = the column in listbox to be returned
'delim = Any delimiter around value
'trm = number of characters to remove from end
Dim strList As String
Dim varSelected As Variant
If LBx.ItemsSelected.Count = 0 Then
'MsgBox "You haven't selected anything"
Else
For Each varSelected In LBx.ItemsSelected
strList = strList & delim & LBx.Column(colmn, varSelected) & delim & ","
Next varSelected
strList = Left$(strList, Len(strList) - Trm)
'MsgBox "You selected the following items:" & vbCrLf & strList
End If
getLBX = strList
End Function
you can then call it with something like
criteria = getLBx(me. List_SriDateSelector,,"#")
it wil return a string of dates Like- #3/1/2018#,#3/31/2018#,#3/30/2018#,#2/6/2018#