Mega Code Archive
Show the Windows Heirarchy
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Title: Show the Windows Heirarchy
Question: There are times when you could do with knowing what different window Handles are for testing messaging apps, etc. Without Loading WinSight (with all it's overheads), or getting WinSpy++, here is a simple digest of Handles, Class Names, and Window Captions.
Answer:
On a Form, place a TreeView Control, and a Button.
Paste in the following 3 procedures/ functions into the implementation Code:
//---
function GetWinInfo(h:HWND):string;
var tmp:PChar;
begin
//Get the HWND value in hex and Decimal
result:=inttohex(h,8);
result:=result+' ('+inttostr(h)+')';
//Get ClassName, and Window Caption
//Allow upto 255 Characters
GetMem(tmp,255);
GetClassName(h,tmp,255);
result:=result+': '+tmp;
tmp[0]:=#0;
GetWindowText(h,tmp,255);
result:=result+' - '+tmp;
FreeMem(tmp);
end;
procedure GetChildren(h:HWND;n:TTreeNode;T:TTreeview);
var Childhw:HWND;
ChildNode:TTreeNode;
begin
//Get any Children
ChildHw:=GetWindow(h,GW_CHILD);
while Childhw32 do
begin
//Add this Handle
ChildNode:=T.Items.AddChild(n,GetWinInfo(Childhw));
//Get any Children - Recursive call...
GetChildren(Childhw,ChildNode,T);
//Get the next window
Childhw:=GetWindow(Childhw,GW_HWNDNEXT);
end;
end;
procedure GetWinTree(T:TTreeview);
var hw:HWND;
node:TTreeNode;
begin
//Loop through all Top Level Windows
hw:=FindWindow(nil,nil);
while hw32 do
begin
//Add this Handle
node:=t.items.Add(nil,GetWinInfo(hw));
//Get any Children
GetChildren(hw,Node,T);
//Get the next window
hw:=GetWindow(hw,GW_HWNDNEXT);
end;
end;
//---
Then put something like this on the ButtonClick Event Handler...
procedure TForm1.Button1Click(Sender: TObject);
begin
TreeView1.Items.clear;
GetWinTree(TreeView1);
end;
You will then have a List of All current Window Handles, with all Child Windows listed with then in their correct places.
This could be expanded with searching/ grouping of like classes, etc. But I leave that to you, here is a starting place.
I have used this at various times to get M$ Class names. For instance, if you are using DAO to automatically configure an Access DB to point it's linked tables at a particular SQL Server, I used this to get the Class name of the SQL Server Login form, so that I could search for it and click the OK button before the user gets to it...
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