Casos De Uso

Imports System.Data.SqlClient

Public Class Form1
Dim Da As New SqlDataAdapter("SELECT IDCategoria, NombreCategoria,Descripcion FROM categorias", cnx)

Sub MUESTRA()
Dim DS As NewDataSet
Da.Fill(DS, "categorias")
DataGridView1.DataSource = DS.Tables(0)
End Sub

Sub LIMPIA()
TextBox1.Clear()
TextBox2.Clear()
TextBox3.Clear()TextBox2.Focus()
End Sub

Private Sub btGuardar_click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btGuardar.Click
Dim sql As String
sql = "insert intocategorias (NombreCategoria,Descripcion) values('" + TextBox2.Text + "' , '" + TextBox3.Text + "')"
If cnx.State = 1 Then cnx.Close()
cnx.Open()
Dim CMD As New SqlCommand(sql,cnx)
CMD.ExecuteNonQuery()
Call LIMPIA()
Call MUESTRA()
End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.LoadCall MUESTRA()
End Sub

Private Sub btBuscar_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btBuscar.Click
Dim VCOD As String, SQL As StringDim DR As SqlDataReader
VCOD = InputBox("INGRESE CÓDIGO DE categorias:", "BUSQUEDA DE categorias")
SQL = "SELECT IDCategoria, NombreCategoria, Descripcion FROM Categorias WHEREIDCategoria='" + VCOD + "'"
If cnx.State = 1 Then cnx.Close()
cnx.Open()
Dim CMD As New SqlCommand(SQL, cnx)
DR.Read()
If DR.HasRows Then
TextBox1.Text =DR(0)
TextBox2.Text = DR(1)
TextBox3.Text = DR(2)
Else
MsgBox("CODIGO NO EXISTE")
End If
End Sub

Private Sub btModificar_Click(ByVal senderAs System.Object, ByVal e As System.EventArgs) Handles btModificar.Click
Dim SQL As String
SQL = "updatecategorias set NombreCategoria='" + TextBox2.Text + "',Descripcion ='" +...