frmclasscourse.vb

师生情况管理系统

        Me.ResumeLayout(False)

    End Sub

#End Region

    Private Sub FrmClassCourse_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        sqlConn = New SqlConnection(FrmMain.DBCONN.DataConStr)
        sqlComm = New SqlCommand("select * from teacherInfo", sqlConn)
        daDate = New SqlDataAdapter("SELECT dbo.courseinfo.CID AS 课程号, dbo.CourseInfo.Cname AS 课程名, dbo.TeacherInfo.Tname AS 教师名, dbo.BookInfo.Bname AS 书名 FROM dbo.CourseInfo, dbo.BookInfo, dbo.TeacherInfo where CourseInfo.CTID = teacherInfo.TID and CourseInfo.BID = BookInfo.BID", sqlConn)
        dsData = New DataSet
        sqlConn.Open()
        daDate.Fill(dsData, "Table")
        dgDate.SetDataBinding(dsData, "Table")

        Dim objReader As SqlDataReader
        objReader = sqlComm.ExecuteReader
        While objReader.Read
            cmbName.Items.Add(objReader(1))
        End While
        objReader.Close()
        cmbName.SelectedIndex = -1

        sqlComm.CommandText = "select Cname from courseinfo"
        objReader = sqlComm.ExecuteReader
        While objReader.Read
            cmbBook.Items.Add(objReader(0))
        End While
        objReader.Close()
        cmbBook.SelectedIndex = -1

        txtID.Enabled = True
        txtName.Enabled = False
        cmbName.Enabled = False
        cmbBook.Enabled = False
        btnSave.Enabled = False
        btnCancel.Enabled = False

        flag = 3
    End Sub

    Private Sub btnExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnExit.Click
        sqlConn.Close()
        Me.Close()
    End Sub

    Private Sub dgDate_CurrentCellChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles dgDate.CurrentCellChanged
        txtID.Text = dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Item(0)
        txtName.Text = dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Item(1)
        cmbName.SelectedItem = dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Item(2)
        cmbBook.SelectedItem = dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Item(3)

    End Sub

    Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click
        flag = 1        'flag为1， 则是添加操作

        txtID.Text = ""
        txtName.Text = ""
        cmbName.SelectedItem = -1
        cmbBook.SelectedItem = -1

        txtID.Enabled = True
        txtName.Enabled = True
        cmbName.Enabled = True
        cmbBook.Enabled = True
        btnSave.Enabled = True
        btnCancel.Enabled = True
        btnAdd.Enabled = False
        btnUpdate.Enabled = False
        btndelete.Enabled = False

    End Sub

    Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click
        If dgDate.CurrentCell.RowNumber < 0 Then
            MsgBox("你还没选择信息")
            Exit Sub
        End If

        flag = 2        'flag为2，则是更新操作
        txtID.Enabled = False
        txtName.Enabled = True
        cmbName.Enabled = True
        cmbBook.Enabled = True
        btnSave.Enabled = True
        btnCancel.Enabled = True
        btnAdd.Enabled = False
        btnUpdate.Enabled = False
        btndelete.Enabled = False
    End Sub

    Private Sub btndelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btndelete.Click
        If dgDate.CurrentCell.RowNumber < 0 Then
            MsgBox("你还没选择信息")
            Exit Sub
        End If

        If MsgBox("你是否真的删除此条信息？", MsgBoxStyle.OKCancel, "删除") = MsgBoxResult.OK Then
            sqlComm.CommandText = "delete courseInfo where CID = '" & txtID.Text & "'"
            daDate.DeleteCommand = sqlComm
            Try
                sqlComm.ExecuteNonQuery()
                MsgBox("成功删除该信息")
                dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Delete()

                txtID.Enabled = False
                txtName.Enabled = False
                cmbName.Enabled = False
                cmbBook.Enabled = False
                btnSave.Enabled = False
                btnCancel.Enabled = True
                btnAdd.Enabled = False
                btnUpdate.Enabled = False
                btndelete.Enabled = False
            Catch ex As Exception
                MsgBox(ex.Message)
            End Try
        End If
    End Sub

    Private Sub btnCancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCancel.Click
        txtID.Enabled = True
        txtName.Enabled = False
        cmbName.Enabled = False
        cmbBook.Enabled = False
        btnSave.Enabled = False
        btnCancel.Enabled = False
        btnAdd.Enabled = True
        btnUpdate.Enabled = True
        btndelete.Enabled = True

        flag = 3
    End Sub
    Private Function check() As Boolean
        If txtID.Text = "" Then
            MsgBox("课程号不能为空！")
            Return False
        End If
        If txtName.Text = "" Then
            MsgBox("课程号不能为空！")
            Return False
        End If
        Return True
    End Function
    Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
        If Me.check() = False Then
            Exit Sub
        End If

        Dim strCTID As String
        Dim strBID As String
        Dim objReader As SqlDataReader
        sqlComm.CommandText = "select TID from courseInfo, teacherInfo where CTID = TID"
        objReader = sqlComm.ExecuteReader
        While objReader.Read
            strCTID = objReader(0)
        End While
        objReader.Close()
        sqlComm.CommandText = "select courseInfo.BID from courseInfo, BookInfo where courseInfo.BID = BookInfo.BID"
        objReader = sqlComm.ExecuteReader()
        While objReader.Read
            strBID = objReader(0)
        End While
        objReader.Close()

        If flag = 1 Then    '添加操作
            Dim objRow As DataRow
            objRow = dsData.Tables(0).NewRow()
            objRow(0) = txtID.Text
            objRow(1) = txtName.Text
            objRow(2) = cmbName.SelectedItem
            objRow(3) = cmbBook.SelectedItem
            dsData.Tables(0).Rows.Add(objRow)

            sqlComm.CommandText = "insert into courseInfo values ('" & txtID.Text & "', '" & txtName.Text & "', '" & strCTID & "', '" & strBID & "')"
            daDate.DeleteCommand = sqlComm

            Try
                sqlComm.ExecuteNonQuery()
                MsgBox("添加成功")

                txtID.Enabled = False
                txtName.Enabled = False
                cmbName.Enabled = False
                cmbBook.Enabled = False
                btnSave.Enabled = False
                btnCancel.Enabled = True
                btnAdd.Enabled = False
                btnUpdate.Enabled = False
                btndelete.Enabled = False
            Catch ex As Exception
                MsgBox(ex.Message)
                dsData.Tables(0).Rows(dsData.Tables(0).Rows.Count - 1).Delete()
            End Try
        End If

        If flag = 2 Then        '更新操作
            dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Item(0) = txtID.Text
            dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Item(1) = txtName.Text
            dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Item(2) = cmbName.SelectedItem
            dsData.Tables(0).Rows(dgDate.CurrentCell.RowNumber).Item(3) = cmbBook.SelectedItem

            sqlComm.CommandText = "update courseInfo set Cname = '" & txtName.Text & "', CTID = '" & strCTID & "', BID = '" & strBID & "' where CID = '" & txtID.Text & "'"
            daDate.UpdateCommand = sqlComm

            Try
                sqlComm.ExecuteNonQuery()
                MsgBox("更新成功")

                txtID.Enabled = False
                txtName.Enabled = False
                cmbName.Enabled = False
                cmbBook.Enabled = False
                btnSave.Enabled = False
                btnCancel.Enabled = True
                btnAdd.Enabled = False
                btnUpdate.Enabled = False
                btndelete.Enabled = False
            Catch ex As Exception
                MsgBox(ex.Message)
            End Try
        End If
    End Sub

    Private Sub txtID_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles txtID.KeyUp
        If flag = 3 Then
            strSelect += txtID.Text
            If strSelect = "" Then
                tableNum = 0
                dsData.Tables(0).Clear()
                daDate.Fill(dsData, "Table")
                dgDate.SetDataBinding(dsData, "Table")
            Else
                tableNum = 1
                sqlComm.CommandText = "SELECT dbo.courseinfo.CID AS 课程号, dbo.CourseInfo.Cname AS 课程名, dbo.TeacherInfo.Tname AS 教师名, dbo.BookInfo.Bname AS 书名 FROM dbo.CourseInfo, dbo.BookInfo, dbo.TeacherInfo where CourseInfo.CTID = teacherInfo.TID and CourseInfo.BID = BookInfo.BID and CID like '" & txtID.Text & "%'"
                daDate.SelectCommand = sqlComm
                If dsData.Tables.Count > 1 Then
                    dsData.Tables(1).Clear()
                End If
                daDate.Fill(dsData, "TableSelect")
                dgDate.SetDataBinding(dsData, "TableSelect")
            End If
        End If

    End Sub
End Class