frmcourse.vb

教务管理系统：学生成绩管理

        Me.TxtCourseID.Name = "TxtCourseID"
        Me.TxtCourseID.Size = New System.Drawing.Size(104, 21)
        Me.TxtCourseID.TabIndex = 0
        Me.TxtCourseID.Text = ""
        '
        'FrmCourse
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(592, 438)
        Me.Controls.Add(Me.GroupBox1)
        Me.Controls.Add(Me.DataGrid1)
        Me.Name = "FrmCourse"
        Me.Text = "课程管理"
        CType(Me.DataGrid1, System.ComponentModel.ISupportInitialize).EndInit()
        Me.GroupBox1.ResumeLayout(False)
        Me.ResumeLayout(False)

    End Sub

#End Region
    Private Sub FrmCourse_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        BindData()
        If DataGrid1.VisibleRowCount > 0 Then
            bindTextBox(0)
        End If
    End Sub

    Private Sub DataGrid1_CurrentCellChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles DataGrid1.CurrentCellChanged
        bindTextBox(Me.DataGrid1.CurrentCell.RowNumber)
    End Sub


    Private Sub BtnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnAdd.Click
        If Me.TxtCourseID.Text.Trim() = String.Empty Then
            MessageBox.Show("课程编号不能为空")
            Me.TxtCourseID.Focus()
        ElseIf Not JudgeInt(TxtCourseID.Text.Trim) Then
            MessageBox.Show("课程编号必须为整数")
            Me.TxtCourseID.Focus()
        ElseIf JudgeKeyExist("courseinfo", "courseid", TxtCourseID.Text.Trim) Then
            MessageBox.Show("课程编号已经存在")
            Me.TxtCourseID.Focus()
        ElseIf Me.TxtCourseName.Text.Trim() = String.Empty Then
            MessageBox.Show("课程名不能为空")
            Me.TxtCourseName.Focus()
        ElseIf Me.TxtCourseTeacher.Text.Trim() = String.Empty Then
            MessageBox.Show("任课教师不能为空")
            Me.TxtCourseTeacher.Focus()
        ElseIf Me.TxtCoursePoint.Text.Trim() = String.Empty Then
            MessageBox.Show("课程学分不能为空")
            Me.TxtCoursePoint.Focus()
        ElseIf Not JudgeInt(TxtCoursePoint.Text.Trim) Then
            MessageBox.Show("课程学分必须为整数")
            Me.TxtCoursePoint.Focus()
        Else
            Me.InsertData()
        End If
    End Sub

    Private Sub BtnEdit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnEdit.Click
        If Me.TxtCourseID.Text.Trim() = String.Empty Then
            MessageBox.Show("课程编号不能为空")
            Me.TxtCourseID.Focus()
        ElseIf Not JudgeInt(TxtCourseID.Text.Trim) Then
            MessageBox.Show("课程编号必须为整数")
            Me.TxtCourseID.Focus()
        ElseIf Not JudgeKeyExist("courseinfo", "courseid", TxtCourseID.Text.Trim) Then
            MessageBox.Show("要更新的记录集不存在")
            Me.TxtCourseID.Focus()
        ElseIf Me.TxtCourseName.Text.Trim() = String.Empty Then
            MessageBox.Show("课程名不能为空")
            Me.TxtCourseName.Focus()
        ElseIf Me.TxtCourseTeacher.Text.Trim() = String.Empty Then
            MessageBox.Show("任课教师不能为空")
            Me.TxtCourseTeacher.Focus()
        ElseIf Me.TxtCoursePoint.Text.Trim() = String.Empty Then
            MessageBox.Show("课程学分不能为空")
            Me.TxtCoursePoint.Focus()
        ElseIf Not JudgeInt(TxtCoursePoint.Text.Trim) Then
            MessageBox.Show("课程学分必须为整数")
            Me.TxtCoursePoint.Focus()
        Else
            Me.UpdateData()
        End If
    End Sub

    Private Sub BtnDel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnDel.Click
        If Me.TxtCourseID.Text.Trim() = String.Empty Then
            MessageBox.Show("课程编号不能为空")
            Me.TxtCourseID.Focus()
        ElseIf Not JudgeInt(TxtCourseID.Text.Trim) Then
            MessageBox.Show("课程编号必须为整数")
            Me.TxtCourseID.Focus()
        ElseIf Not JudgeKeyExist("courseinfo", "courseid", TxtCourseID.Text.Trim) Then
            MessageBox.Show("要更新的记录集不存在")
            Me.TxtCourseID.Focus()
        Else
            If MessageBox.Show("确定要删除？", "删除确认", MessageBoxButtons.OKCancel, MessageBoxIcon.Warning, MessageBoxDefaultButton.Button2) = DialogResult.OK Then
                Me.DeleteData()
            End If
        End If
    End Sub

    Private Sub BtnExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnExit.Click
        Me.Close()
    End Sub

    Private Sub BindData()
        Try
            Dim sql As String = "select Courseid as '课程编号',Coursename as '课程名称',courseteacher as '任课教师',Coursepoint as '课程学分',courseabout as '相关说明' from Courseinfo"
            Dim dt As DataTable = GetDataTable(sql)
            If dt.Rows.Count <> 0 Then
                DataGrid1.DataSource = dt
            End If
        Catch ex As Exception
            WriteErr(ex)
        End Try

    End Sub


    Private Sub bindTextBox(ByVal row As Int16)
        Me.TxtCourseID.Text = Me.DataGrid1.Item(row, 0)
        Me.TxtCourseName.Text = Me.DataGrid1.Item(row, 1)
        Me.TxtCourseTeacher.Text = Me.DataGrid1.Item(row, 2)
        Me.TxtCoursePoint.Text = Me.DataGrid1.Item(row, 3)
        Me.TxtCourseAbout.Text = Me.DataGrid1.Item(row, 4)
    End Sub

    Private Sub InsertData()

        Dim CourseID As Int16 = Int16.Parse(TxtCourseID.Text.Trim)
        Dim CourseName As String = TxtCourseName.Text.Trim
        Dim CourseTeacher As String = TxtCourseTeacher.Text.Trim
        Dim CoursePoint As String = TxtCoursePoint.Text.Trim
        Dim CourseAbout As String = TxtCourseAbout.Text.Trim

        Dim value As String = CourseID.ToString + ",'" + CourseName + "','" + CourseTeacher + "'," + CoursePoint + ",'" + CourseAbout + "'"

        Dim sql As String = "INSERT INTO COURSEINFO (COURSEID, COURSENAME,COURSETEACHER,COURSEPOINT,COURSEABOUT) VALUES(" + value + ")"

        Dim sqlCmd As New SqlCommand
        sqlCmd.Connection = SqlCon
        sqlCmd.CommandText = sql

        Try
            SqlCon.Open()
            sqlCmd.ExecuteNonQuery()
            MessageBox.Show("添加记录成功")
        Catch ex As Exception
            MessageBox.Show("添加记录失败")
            WriteErr(ex)
        Finally
            SqlCon.Close()
        End Try
        BindData()
    End Sub

    Private Sub UpdateData()

        Dim CourseID As Int16 = Int16.Parse(TxtCourseID.Text.Trim)
        Dim CourseName As String = TxtCourseName.Text.Trim
        Dim CourseTeacher As String = TxtCourseTeacher.Text.Trim
        Dim CoursePoint As String = TxtCoursePoint.Text.Trim
        Dim CourseAbout As String = TxtCourseAbout.Text.Trim

        Dim sql As String = "UPDATE COURSEINFO SET COURSENAME='" + CourseName + "',COURSETEACHER='" + CourseTeacher + "',COURSEPOINT=" + CoursePoint + ",COURSEABOUT='" + CourseAbout + "' WHERE COURSEID= " + CourseID.ToString

        Dim sqlCmd As New SqlCommand
        sqlCmd.Connection = SqlCon
        sqlCmd.CommandText = sql

        Try
            SqlCon.Open()
            sqlCmd.ExecuteNonQuery()
            MessageBox.Show("修改记录成功")
        Catch ex As Exception
            MessageBox.Show("修改记录失败")
            WriteErr(ex)
        Finally
            SqlCon.Close()
        End Try
        BindData()
    End Sub

    Private Sub DeleteData()

        Dim CourseID As Int16 = Int16.Parse(TxtCourseID.Text.Trim)

        Dim sql As String = "DELETE FROM COURSEINFO WHERE COURSEID= " + CourseID.ToString()

        Dim sqlCmd As New SqlCommand
        sqlCmd.Connection = SqlCon
        sqlCmd.CommandText = sql

        Try
            SqlCon.Open()
            sqlCmd.ExecuteNonQuery()
            MessageBox.Show("删除记录成功")
        Catch ex As Exception
            MessageBox.Show("删除记录失败")
            WriteErr(ex)
        Finally
            SqlCon.Close()
        End Try
        BindData()
        bindTextBox(0)
    End Sub
End Class