DOCUMENT:Q161161  14-JUL-1997  [vbwin]
TITLE   :HOWTO: Search a ListBox Control Quickly
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:5.0
OPER/SYS:WINDOWS
KEYWORDS:kbprg vb5all vb5howto VBKBCtrl VBKBInt VBKBListBox VBKBStd kbhowto

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The information in this article applies to:

 - Microsoft Visual Basic Control Creation, Learning, Professional, and
   Enterprise Editions for Windows, version 5.0
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SUMMARY
=======

A popular item in a user interface is to "link" a text box to a list box so
the nearest match in the list box is selected when the user types text into
the text box. This technique can be implemented using pure Visual Basic
code, but the Windows API provides a quicker and easier way to do this.

MORE INFORMATION
================

The technique calls the Windows API SendMessage function using the
LB_FINDSTRING message for a list box to locate a partial match for a string
in the list box. SendMessage requires the following parameters:

      SendMessage(hWnd, LB_FINDSTRING, wParam, lParam) where

         hWnd    - is the hWnd of the list box.
         wParam  - is an integer that specifies the starting point for the
                   search. Use -1 to search the whole list box.
         lParam  - is a long pointer to the string to find.

Step-by-Step Example
--------------------

1. Start a new Standard EXE project. Form1 is added by default.

2. Add a TextBox control (Text1) and a ListBox control (List1) to Form1.

3. Add the following code to the General Declarations section of Form1:

      Const LB_FINDSTRING = &H18F
      Private Declare Function SendMessage Lib "User32" _
             Alias "SendMessageA" _
         (ByVal hWnd As Long, _
          ByVal wMsg As Integer, _
          ByVal wParam As Integer _
          lParam As Any) As Long

      Private Sub Form_Load()
         List1.Clear
         List1.AddItem "Apples"
         List1.AddItem "Banana"
         List1.AddItem "Bread"
         List1.AddItem "Break"
         Text1.Text = ""
      End Sub

      Private Sub Text1_Change()
         List1.ListIndex = SendMessage(List1.hWnd, LB_FINDSTRING, -1, _
            ByVal CStr(Text1.Text))
      End Sub

5. Press the F5 key to run the program. Typing text into the text box
   selects the first item in the list box which matches the text in the
   text box.
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Keywords            : kbprg vb5all vb5howto VBKBCtrl VBKBInt VBKBListBox VBKBStd kbhowto
Version             : 5.0
Platform            : WINDOWS
Issue type          : kbhowto

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Copyright Microsoft Corporation 1997.