用如下编码导入excel表数据不能去除重复的行

Dim Book As New XLS.Book("D:\\Documents\\管理项目2\\资料.xls")
Dim Sheet As XLS.Sheet = Book.Sheets(0)
Tables("期初").StopRedraw()   \'注意以下数组中列名称的顺序,必须和Excel表中的列顺序一致
Dim nms() As String = {"类别","品名","规格","型号","材质","单位"}
            \'注意下面的循环变量从1开始,而不是从0开始,因为Excel表的第一行是标题
For n As Integer = 1 To Sheet.Rows.Count -1
    Dim r As Row = Tables("资料").AddNew()
    For m As Integer = 0 To nms.Length - 1
         r(nms(m)) = Sheet(n,m).Value
    Next
Next
Tables("资料").ResumeRedraw()

大概如此，希望你能理解：

Dim Book As New XLS.Book("D:\\Documents\\管理项目2\\资料.xls")
Dim Sheet As XLS.Sheet = Book.Sheets(0)
Tables("期初").StopRedraw()
Dim nms() As String = {"类别","品名","规格","型号","材质","单位"}
For n As Integer = 1 To Sheet.Rows.Count - 1
    Dim Filter As String
    For m As Integer = 0 To nms.Length - 1
        If m > 0 Then
            Filter = Filter & " And "
        End If
        Filter = Filter & nms(m) & " = \'" & sheet(n,m).Value & "\'"
    Next
    If DataTables("资料").Find(Filter) Is Nothing Then
        Dim r As Row = Tables("资料").AddNew()
        For m As Integer = 0 To nms.Length - 1
            r(nms(m)) = Sheet(n,m).Value
        Next
    End If
Next
Tables("资料").ResumeRedraw()