C# と VB.NET の質問掲示板

■No81738 (Artor さん) に返信

スマートか分かりませんがこんなのはどうでしょう？

        Dim tbl As New DataTable()
        With tbl.Columns
            .Add("CD", GetType(String))
            .Add("DT", GetType(String))
            .Add("TB", GetType(String))
        End With

        tbl.Rows.Add("001", "鈴木", "A.name")
        tbl.Rows.Add("001", "田中", "A.name")
        tbl.Rows.Add("002", "東京", "A.front")
        tbl.Rows.Add("003", "経理", "A.buka")
        tbl.Rows.Add("003", "人事", "A.buka")

        Dim whr As New System.Text.StringBuilder
        For Each itm In (From r In tbl.AsEnumerable
                Select CD = r.Field(Of String)("CD"), DT = r.Field(Of String)("DT"), TB = r.Field(Of String)("TB")
                Let Value = String.Format("{0}='{1}'", TB, DT)
                Group Value By CD Into Values = Group)
            If whr.Length > 0 Then whr.AppendLine(" AND ")
            If itm.Values.Count > 1 Then whr.Append("(")
            whr.Append(String.Join(" OR ", itm.Values.ToArray))
            If itm.Values.Count > 1 Then whr.Append(")")
            whr.AppendLine()
        Next

        Console.WriteLine(whr.ToString)