Visual Basic

Imports MySql.Data.MySqlClient

Public Class InputDO
    Public Shared MyConnString As String = "Server=;Database=logistic_sysdb;Uid=root;Pwd=;"
    Public Shared ObjMyConn As New MySqlConnection
    Public Shared ObjComm As New MySqlCommand
    Public Shared ObjRead As MySqlDataReader
    Public Shared SQL As String

    Dim ObjAdapter As MySqlDataAdapter
    Dim ds As DataSet
    Dim dt As DataTable
    Dim dt1 As DataTable

    Private Sub InputDO_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim i As Integer

        ObjMyConn = New MySqlConnection(MyConnString)

        'Load the information into Lorry Number Combobox
        Try
            SQL = "SELECT * FROM lorry_detail"
            ds = New DataSet
            ObjAdapter = New MySqlDataAdapter(SQL, ObjMyConn)
            ObjAdapter.Fill(ds, "Lorry_Number")
            dt = ds.Tables("Lorry_Number")

            For i = 0 To dt.Rows.Count - 1
                ComboBox1.Items.Add(dt.Rows(i).Item(0))
            Next

        Catch ex As Exception
            MsgBox("Error: " & ex.Source & ": " & ex.Message, MsgBoxStyle.OkOnly, "Connection Error !!")
        End Try

        Try
            SQL = "SELECT * FROM company_detail"

            ds = New DataSet
            ObjAdapter = New MySqlDataAdapter(SQL, ObjMyConn)
            ObjAdapter.Fill(ds, "Client_Company")
            dt1 = ds.Tables("Client_Company")

        Catch ex As Exception
            MsgBox("Error: " & ex.Source & ": " & ex.Message, MsgBoxStyle.OkOnly, "Connection Error !!")

        End Try

    End Sub

    Private Sub ComboBox2_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ComboBox2.TextChanged
        Dim x As String ' x = The Client Company name that stored at dt1
        Dim i As Integer

        x = ComboBox2.Text

        For i = 0 To dt1.Rows.Count - 1
            If x = dt1.Rows(i).Item(1) Then
                ComboBox2.Items.Add(dt1.Rows(i).Item(1))
            End If

        Next

    End Sub
End Class