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预览时的错误提示
以下是我的代码:我测试过,第一层for each正常,第二层出错,找一上午没不到原因,请帮我看一下,错在哪里,谢谢
Dim cmd As New SQLCommand
Dim dt As DataTable
cmd.C
cmd.CommandText = "SELECT * From {cd} where sjcdmc is null"
dt = cmd.ExecuteReader()
Dim cmd1 As New SQLCommand
Dim dt1 As DataTable
cmd1.C
For Each dr As DataRow In dt.DataRows
tpb.pages.add(dr("cdmc"),dr("cdsm"),dr("cdtp")).Collapsed = True
cmd1.CommandText = "SELECT * From {cd} where sjcdmc ='" & dr("cdmc") & "'"
dt1 = cmd1.ExecuteReader()
For Each dr1 As DataRow In dt1.DataRows
tpb.Pages("cdmc").Links.Add(dr1("cdmc"), dr1("cdsm"))
Next
Next