VB .NET - Comandos SQL na Prática

Imports System.Data.OleDb

Public Class frmSQL

    Inherits System.Windows.Forms.Form

    Dim conn As New System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & _

                                                      Replace(Application.StartupPath, "bin", "") & _

                                                      "Cadastro.mdb;Mode=ReadWrite;Persist Security Info=False")

    Private Sub ExecuteBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExecuteBtn.Click

        Dim DataSet As New DataSet

        Dim DataTable As New DataTable()

        'Declara a OleDbCommand Object

        Dim cmd As New System.Data.OleDb.OleDbCommand(txtSqlClientes.Text, conn)

        Dim DataAdapter As New OleDbDataAdapter(txtSqlClientes.Text, conn)

        Try

            Select Case UCase(Mid(Trim(txtSqlClientes.Text), 1, 6))

                Case "SELECT"

                    conn.Open()

                    cmd.ExecuteNonQuery()

                    DataAdapter.Fill(DataTable)

                    Me.DgViewClientes.DataSource = DataTable

                    conn.Close()

                Case "INSERT"

                    conn.Open()

                    cmd.ExecuteNonQuery()                   

                    conn.Close()

                    MsgBox("Registro inserido com sucesso.", MsgBoxStyle.Exclamation)

                Case "UPDATE"

                    conn.Open()

                    cmd.ExecuteNonQuery()                   

                    conn.Close()

                    MsgBox("Registro alterado com sucesso.", MsgBoxStyle.Exclamation)

                Case "DELETE"

                    conn.Open()

                    cmd.ExecuteNonQuery()                                    

                    conn.Close()

                    MsgBox("Registro deletado com sucesso.", MsgBoxStyle.Exclamation)

            End Select

        Catch ex As Data.OleDb.OleDbException

            MsgBox(ex.Message)

        End Try

    End Sub

    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click

        Dim DataSet As New DataSet

        Dim DataTable As New DataTable()

        'Declara a OleDbCommand Object

        Dim cmd As New System.Data.OleDb.OleDbCommand(txtSqlGrupos.Text, conn)

        Dim DataAdapter As New OleDbDataAdapter(txtSqlGrupos.Text, conn)

        Try

            Select Case UCase(Mid(Trim(txtSqlGrupos.Text), 1, 6))

                Case "SELECT"

                    conn.Open()

                    cmd.ExecuteNonQuery()

                    DataAdapter.Fill(DataTable)

                    Me.DgviewGrupos.DataSource = DataTable

                    conn.Close()

                Case "INSERT"

                    conn.Open()

                    cmd.ExecuteNonQuery()                                    

                    conn.Close()

                    MsgBox("Registro inserido com sucesso.", MsgBoxStyle.Exclamation)                   

                Case "UPDATE"

                    conn.Open()

                    cmd.ExecuteNonQuery()                                       

                    conn.Close()

                    MsgBox("Registro alterado com sucesso.", MsgBoxStyle.Exclamation)

                Case "DELETE"

                    conn.Open()

                    cmd.ExecuteNonQuery()                                       

                    conn.Close()

                    MsgBox("Registro deletado com sucesso.", MsgBoxStyle.Exclamation)

            End Select

        Catch ex As Data.OleDb.OleDbException

            MsgBox(ex.Message)

        End Try

    End Sub

    Private Sub btnQuerys_Click(sender As System.Object, e As System.EventArgs) Handles btnQuerys.Click

        frmQuerys.ShowDialog()

    End Sub

End Class

Public Class frmQuerys

    Private Sub btnConcluir_Click(sender As System.Object, e As System.EventArgs) Handles btnConcluir.Click

        If Me.RadioButton1.Checked Then

            frmSQL.txtSqlClientes.Text = RadioButton1.Text

        End If

        If Me.RadioButton2.Checked Then

            frmSQL.txtSqlClientes.Text = RadioButton2.Text

        End If

        If Me.RadioButton3.Checked Then

            frmSQL.txtSqlClientes.Text = RadioButton3.Text

        End If

        If Me.RadioButton4.Checked Then

            frmSQL.txtSqlGrupos.Text = RadioButton4.Text

        End If

        If Me.RadioButton5.Checked Then

            frmSQL.txtSqlGrupos.Text = RadioButton5.Text

        End If

        If Me.RadioButton6.Checked Then

            frmSQL.txtSqlGrupos.Text = RadioButton6.Text

        End If

        Me.Dispose()

    End Sub

End Class

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