[مصطفى الجازوي]

شكرا علي المشاركة
وهذا هو كود الاستعارة
 sql = "select * from Retieval  where Book_no=" & TextBox1.Text
        DataAdapter.SelectCommand = New SqlCommand(sql, connection)
        DataSet.Clear()
        DataAdapter.Fill(DataSet, "Retieval")
        If (DataSet.Tables("Retieval").Rows.Count = -1) Then
            MsgBox("المشترك غير موجود ")
            Exit Sub
        End If
        '''''''''''''''
        'كود التأكد من أن الطالب لم يتعدى 3 كتب

        sql = "select  count (*) from Book  where Book_no=" & TextBox1.Text
        DataAdapter.SelectCommand = New SqlCommand(sql, connection)
        DataSet.Clear()
        connection.Open()

        num = DataAdapter.SelectCommand.ExecuteScalar
        connection.Close()
        '''''''''''''''
        If IsDBNull(num) Then
            num = 0
        Else
            If num >= 3 Then
                MsgBox("لايمكنك الأستعارة ")
                Exit Sub
            End If
        End If
        ''''''''''
        sql = " insert into Retieval (Book_no,Card_no,NO_borrowed,Bo_date1,Bo_date2,Bo_date3,Bo_Day)  values (" & TextBox1.Text & ",'" & TextBox2.Text & "','" & TextBox3.Text & "', "
        sql = sql & DateTimePicker1.Value.Date & "," & DateTimePicker2.Value.Date & ", " & DateTimePicker3.Value.Date & ", "
        sql = sql & NumericUpDown1.Value & ")"
        DataAdapter.InsertCommand = New SqlCommand(sql, connection)
        connection.Open()
        DataAdapter.InsertCommand.ExecuteNonQuery()
        connection.Close()
        MsgBox("تمت الأستعارة بنجاح")