各教科 (英語、数学など) ごとにテーブルが作成され、学生テーブルは各教科テーブルに関連付けられています。誰かが親切に以下のコードを編集して、削除コマンドを実行して、これらの複数のテーブルから記録します。
重要な問題の 1 つは、削除コマンドを実行して、新しいサブジェクトが導入されたときに後で作成される追加のサブジェクト テーブルから関連するレコードを削除できるようにする方法があることです。
Dim cd As String
If txtName.Text = "" And cboDay.Text = "" And cboMonth.Text = "" And txtYear.Text = "" And lblAge.Text = "" And radioMale.Checked = False Or RadioFemale.Checked = False And txtGName.Text = "" And txtMPhone.Text = "" And txtEmail.Text = "" And txtAddress.Text = "" And txtCity.Text = "" And cboRegion.Text = "" And PictureBox1.ImageLocation = "" Then
MessageBox.Show("There is no record selected to delete. Search for the record to delete.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
Else
cd = MessageBox.Show("You are about to delete this record. Are you sure you want to delete?", "Confirm Delete", MessageBoxButtons.YesNo, MessageBoxIcon.Question)
If cd = vbYes Then
cmd = New SqlCommand("Delete from StudentDetails.Registration where StudentId='" & txtStudentId.Text & "'", cn)
cmd.ExecuteNonQuery()
cmd = New SqlCommand("Delete from StudentDetails.Students where StudentId='" & txtStudentId.Text & "'", cn)
cmd.ExecuteNonQuery()
cmd = New SqlCommand("Delete from ProgramDetails.EnglishLanguage where StudentId='" & txtStudentId.Text & "'", cn)
cmd.ExecuteNonQuery()
MessageBox.Show("Record deleted", "Deleted", MessageBoxButtons.OK, MessageBoxIcon.Information)
Showgrid()
txtStudentId.Clear()
txtName.Clear()
cboDay.Text = ""
cboMonth.Text = ""
lblAge.Text = ""
txtNationality.Clear()
If radioMale.Checked = True Then
Sex = ""
End If
cboStudentType.Text = ""
cboHouse.Text = ""
cboRoom.Text = ""
txtGName.Clear()
txtMPhone.Clear()
txtHPhone.Clear()
txtEmail.Clear()
txtAddress.Clear()
txtCity.Clear()
cboRegion.Text = ""
PictureBox1.Image = PictureBox1.ErrorImage
txtStudentId.Focus()
End If
End If