Question : Making a Button on a Form Visible After Checking the Text Property of a ComboBox on the Form

I have a Form1 in a Visual Basic Application Visual Studio 2008 that has three controls on it:
A comboBox1, a Button1 and a Button2.
The Default Visible Property of Button2 is False (That is Button2 is not visible when Form1 loads).

The collection of strings for Combox1 has two items “Apple” and “Mango”

I need help with code for the click event of a Button1 which will check the value of the current text property of ComboBox1 and make Button2 Visible if the current Text Property of ComboBox1 is Apple.

I have tried the following code but it does not work.

Private Sub

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

If Combox1.Text = "Apple" Then
Button2.Visible = True
End If
MsgBox (Cobox1.Text)

End Sub

The above does not work even though Clicking Button1 does show a MsgBox with “Apple” on it.

         
          Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
       
        If Combox1.Text = "Apple" Then
            Button2.Visible = True
        End If
MsgBox (CoboBox1.Text)
' the message box here does show "Apple" cofirming that 
' the text proberty of ComboBox1 is "Apple" at the 
' time of Button1 Click Event

End Sub

Answer : Making a Button on a Form Visible After Checking the Text Property of a ComboBox on the Form

My simple sample

Create a counter.
In qrband.beforeprint inc the counter
In qrband.afterprint check the counter, and if it's as needed force a new page.

See the code example

                       
         
           
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             unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, QuickRpt, QRCtrls, ExtCtrls, DB, DBTables;

type
  TForm1 = class(TForm)
    Table1: TTable;
    QuickRep1: TQuickRep;
    QRBand2: TQRBand;
    QRDBText1: TQRDBText;
    QRDBText2: TQRDBText;
    QRDBText3: TQRDBText;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
    procedure QRBand2BeforePrint(Sender: TQRCustomBand; var PrintBand: Boolean);
    procedure QRBand2AfterPrint(Sender: TQRCustomBand; BandPrinted: Boolean);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  i: Integer;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  i := 0;
  QuickRep1.Preview;
end;

procedure TForm1.QRBand2AfterPrint(Sender: TQRCustomBand; BandPrinted: Boolean);
begin
  if i mod 5 = 0 then
    QuickRep1.NewPage;
end;

procedure TForm1.QRBand2BeforePrint(Sender: TQRCustomBand; var PrintBand: Boolean);
begin
  Inc(i);
end;

end.


the form

object Form1: TForm1
  Left = 245
  Top = 92
  Caption = 'Form1'
  ClientHeight = 464
  ClientWidth = 854
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  Scaled = False
  PixelsPerInch = 96
  TextHeight = 13
  object QuickRep1: TQuickRep
    Left = 76
    Top = 54
    Width = 794
    Height = 1123
    Frame.Color = clBlack
    Frame.DrawTop = False
    Frame.DrawBottom = False
    Frame.DrawLeft = False
    Frame.DrawRight = False
    DataSet = Table1
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -13
    Font.Name = 'Arial'
    Font.Style = []
    Functions.Strings = (
      'PAGENUMBER'
      'COLUMNNUMBER'
      'REPORTTITLE')
    Functions.DATA = (
      '0'
      '0'
      #39#39)
    Options = [FirstPageHeader, LastPageFooter]
    Page.Columns = 1
    Page.Orientation = poPortrait
    Page.PaperSize = A4
    Page.Values = (
      100.000000000000000000
      2970.000000000000000000
      100.000000000000000000
      2100.000000000000000000
      100.000000000000000000
      100.000000000000000000
      0.000000000000000000)
    PrinterSettings.Copies = 1
    PrinterSettings.OutputBin = Auto
    PrinterSettings.Duplex = False
    PrinterSettings.FirstPage = 0
    PrinterSettings.LastPage = 0
    PrinterSettings.UseStandardprinter = False
    PrinterSettings.UseCustomBinCode = False
    PrinterSettings.CustomBinCode = 0
    PrinterSettings.ExtendedDuplex = 0
    PrinterSettings.UseCustomPaperCode = False
    PrinterSettings.CustomPaperCode = 0
    PrinterSettings.PrintMetaFile = False
    PrinterSettings.PrintQuality = 0
    PrinterSettings.Collate = 0
    PrinterSettings.ColorOption = 0
    PrintIfEmpty = True
    SnapToGrid = True
    Units = MM
    Zoom = 100
    PrevFormStyle = fsNormal
    PreviewInitialState = wsNormal
    PrevInitialZoom = qrZoomToFit
    object QRBand2: TQRBand
      Left = 38
      Top = 38
      Width = 718
      Height = 40
      Frame.Color = clBlack
      Frame.DrawTop = False
      Frame.DrawBottom = False
      Frame.DrawLeft = False
      Frame.DrawRight = False
      AfterPrint = QRBand2AfterPrint
      AlignToBottom = False
      BeforePrint = QRBand2BeforePrint
      Color = clWhite
      TransparentBand = False
      ForceNewColumn = False
      ForceNewPage = False
      Size.Values = (
        105.833333333333300000
        1899.708333333333000000)
      PreCaluculateBandHeight = False
      KeepOnOnePage = False
      BandType = rbDetail
      object QRDBText1: TQRDBText
        Left = 18
        Top = 12
        Width = 44
        Height = 17
        Frame.Color = clBlack
        Frame.DrawTop = False
        Frame.DrawBottom = False
        Frame.DrawLeft = False
        Frame.DrawRight = False
        Size.Values = (
          44.979166666666670000
          47.625000000000000000
          31.750000000000000000
          116.416666666666700000)
        Alignment = taLeftJustify
        AlignToBand = False
        AutoSize = True
        AutoStretch = False
        Color = clWhite
        DataSet = Table1
        DataField = 'CustNo'
        Transparent = False
        WordWrap = True
        FontSize = 10
      end
      object QRDBText2: TQRDBText
        Left = 104
        Top = 12
        Width = 56
        Height = 17
        Frame.Color = clBlack
        Frame.DrawTop = False
        Frame.DrawBottom = False
        Frame.DrawLeft = False
        Frame.DrawRight = False
        Size.Values = (
          44.979166666666670000
          275.166666666666700000
          31.750000000000000000
          148.166666666666700000)
        Alignment = taLeftJustify
        AlignToBand = False
        AutoSize = True
        AutoStretch = False
        Color = clWhite
        DataSet = Table1
        DataField = 'Company'
        Transparent = False
        WordWrap = True
        FontSize = 10
      end
      object QRDBText3: TQRDBText
        Left = 454
        Top = 11
        Width = 24
        Height = 17
        Frame.Color = clBlack
        Frame.DrawTop = False
        Frame.DrawBottom = False
        Frame.DrawLeft = False
        Frame.DrawRight = False
        Size.Values = (
          44.979166666666670000
          1201.208333333333000000
          29.104166666666670000
          63.500000000000000000)
        Alignment = taLeftJustify
        AlignToBand = False
        AutoSize = True
        AutoStretch = False
        Color = clWhite
        DataSet = Table1
        DataField = 'City'
        Transparent = False
        WordWrap = True
        FontSize = 10
      end
    end
  end
  object Button1: TButton
    Left = 10
    Top = 12
    Width = 75
    Height = 25
    Caption = 'Button1'
    TabOrder = 1
    OnClick = Button1Click
  end
  object Table1: TTable
    Active = True
    DatabaseName = 'DBDEMOS'
    TableName = 'customer.db'
    Left = 228
    Top = 120
  end
end

           
         