Atlanta Custom Software Development 

 
   Search        Code/Page
 

User Login
Email

Password

 

Forgot the Password?
Services
» Web Development
» Maintenance
» Data Integration/BI
» Information Management
Programming
  Database
Automation
OS/Networking
Graphics
Links
Tools
» Regular Expr Tester
» Free Tools

Open the list portion of a ComboBox control

Total Hit ( 2520)

Rate this article:     Poor     Excellent 

 Submit Your Question/Comment about this article

Rating


 


To programmatically open and close the list portion of a ComboBox control, all you need is sending the CB_SHOWDROPDOWN message to the control. Here is a routine that encapsulate the SendMessage API function:

Click here to copy the following block
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal _
  hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
  lParam As Any) As Long
Const CB_SHOWDROPDOWN = &H14F
Const CB_GETDROPPEDSTATE = &H157

' Show or hide the list portion of a combobox
  
Sub ComboBoxOpenList(cbo As ComboBox, Optional showIt As Boolean = True)
  SendMessage cbo.hwnd, CB_SHOWDROPDOWN, showIt, ByVal 0&
End Function

Retrieving the current visibility state of the list portion of a ComboBox can be done by sending a message, too. Here is a wrapper function that does it all:

Click here to copy the following block
' Returns True if the list portion of a combobox is visible

Function ComboBoxIsListVisible(cbo As ComboBox) As Boolean
  ComboBoxIsListVisible = SendMessage(cbo.hwnd, CB_GETDROPPEDSTATE, 0, _
    ByVal 0&)
End Function


Submitted By : Nayan Patel  (Member Since : 5/26/2004 12:23:06 PM)

Job Description : He is the moderator of this site and currently working as an independent consultant. He works with VB.net/ASP.net, SQL Server and other MS technologies. He is MCSD.net, MCDBA and MCSE. In his free time he likes to watch funny movies and doing oil painting.
View all (893) submissions by this author  (Birth Date : 7/14/1981 )


Home   |  Comment   |  Contact Us   |  Privacy Policy   |  Terms & Conditions   |  BlogsZappySys

© 2008 BinaryWorld LLC. All rights reserved.