主题：如何比对七个datatable中相同的身份证号的记录？

Dim s As New List (Of String)
For Each dt As DataTable In DataTables
    If dt.DataCols.Contains("身份证号码") Then
        For Each dr As DataRow In dt.DataRows
            s.Add(dr("身份证号码"))
        Next
    End If
Next

Dim str As String
Dim i,j As Integer
For i = 0 To s.Count - 1
    For j = 0 To i - 1
        If s(i) = s(j) Then
            Exit For
        End If
    Next
    If i <> j Then
        str = str & s(i) & "|"
    End If
Next
str = str.TrimEnd("|")
MessageBox.Show(str)