Select all text in edit contol by clicking Ctrl+A - winapi

Question

How to select all text in edit control by pressing Ctrl+A?
I can catch Ctrl+A for parent window in WndProc.
But I don't know how to catch ctrl+a which are applied for edit control.
Also I tried to use accelerators, but again it applies only for parent window.
Thanks.
EDIT: 1-st the simplest method
This method Based on #phord's answers in this question:
win32 select all on edit ctrl (textbox)
while( (bRet = GetMessage( &msg, NULL, 0, 0 )) != 0)
{
if (bRet == -1)
{
// handle the error and possibly exit
}
else
{
if (msg.message == WM_KEYDOWN && msg.wParam == 'A' && GetKeyState(VK_CONTROL) < 0)
{
HWND hFocused = GetFocus();
wchar_t className[6];
GetClassName(hFocused, className, 6);
if (hFocused && !wcsicmp(className, L"edit"))
SendMessage(hFocused, EM_SETSEL, 0, -1);
}
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
EDIT: 2-nd method
Need to use CreateAcceleratorTable + TranslateAccelerator functions:
//global variables:
enum {ID_CTRL_A = 1};
HACCEL accel;
//main procedure
ACCEL ctrl_a;
ctrl_a.cmd = ID_CTRL_A; // Hotkey ID
ctrl_a.fVirt = FCONTROL | FVIRTKEY;
ctrl_a.key = 0x41; //'A' key
accel = CreateAcceleratorTable(&ctrl_a, 1); //we have only one hotkey
//How GetMessage loop looks
while( (bRet = GetMessage( &msg, NULL, 0, 0 )) != 0)
{
if (bRet == -1)
{
// handle the error and possibly exit
}
else
{
if (!TranslateAccelerator(hWnd, accel, &msg))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
}
//in WndProc we must add next cases
case WM_COMMAND:
{
if (LOWORD(wParam) == ID_CTRL_A && HIWORD(wParam) == 1)
{
//on which control there was pressed Ctrl+A
//there is no way of getting HWND through wParam and lParam
//so we get HWND which currently has focus.
HWND hFocused = GetFocus();
wchar_t className[6];
GetClassName(hFocused, className, 6);
if (hFocudsed && !wcsicmp(className, L"edit"))
SendMessage(hFocused, EM_SETSEL, 0, -1);
}
}
break;
case WM_DESTROY:
{
DestroyAcceleratorTable(accel);
PostQuitMessage(0);
}
break;
As you can see this is pretty simple.

Answer 1

No need to handle WM_KEYDOWN! I know that most examples here (and CodeProject and many other places) all say there is, but it does not cure the beep that results whenever a WM_CHAR arises that is not handled.
Instead, try this:
LRESULT CALLBACK Edit_Prc(HWND hwnd,UINT msg,WPARAM wParam,LPARAM lParam){
if(msg==WM_CHAR&&wParam==1){SendMessage(hwnd,EM_SETSEL,0,-1); return 1;}
else return CallWindowProc((void*)WPA,hwnd,msg,wParam,lParam);
}
Remember to subclass the EDIT control to this Edit_Prc() using WPA=SetWindowLong(...) where WPA is the window procedure address for CallWindowProc(...)

Answer 2

First change the WindowProc for the edit control:
if (!(pEditProc = (WNDPROC)SetWindowLong(hEdit, GWL_WNDPROC, (LONG)&EditProc)))
{
assert(false);
return false;
}
Then in the new window proc, process the ctrl+a:
LRESULT CALLBACK EditProc( HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam )
{
if (msg == WM_KEYDOWN) {
if (GetKeyState(VK_CONTROL) & 0x8000 && wParam == 'A') {
SendMessage(hwnd, EM_SETSEL, 0, -1);
}
}
return CallWindowProc(pEditProc, hwnd, msg, wParam, lParam);
}

Answer 3

Good News!
It seems Edit Controls (not multiline) now support Ctrl + A natively on Win10.
My current Windows SDK version is 10.0.17763.0.
Only tested on simple GUI APPs created with pure Windows API.
MFC APPs should have the same result.
The test binary platform is x86, and OS is Win10 x64.

Answer 4

Noob proof version?
I have written my own version using an accelerator table aswell.
This cleans out the WinMain a bit, and I tried to make everything as n00b proof as possible (since I am one).
Also the enum is ommited, since it is not needed.
As stated I am only a beginner in using the winapi, so please by all means
correct me if I am wrong.
In "Resource.h" I define two ID's
One for the accelerator table we will be using,
and one for the selectall command we will be using.
Inside Resource.h:
#define IDR_ACCEL1 101
#define ID_SELECT_ALL 9003
Then inside of the resource file (in vs2017 this is PROJECTNAME.rc)
we define the accelerator table.
PROJECTNAME.rc:
IDR_ACCEL1 ACCELERATORS
{
0x41, ID_SELECT_ALL, VIRTKEY, CONTROL // ctrl-A
}
Description
0x41 is virtkey 'a'.
ID_SELECT_ALL (will be the ID of the command, this should be the ID we defined in the Resource.h file.
The VIRTKEY keyword indicated that the 0x41 should be interpreted as a virtual key.
CONTROL is the modifier needed to combine the a with (ctrl+a).
Then inside the WinMain function load the accelerator:
HACCEL hAccel = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDR_ACCEL1));
if (hAccel == NULL)
{
MessageBox(NULL, _T("Failed to load accelerator table!"),_T("Error"), MB_OK | MB_ICONEXCLAMATION);
return 0;
}
Note: after trying to define hAccel we do a check to see if a valid handle has be assigned.
While this is not needed, I believe it's better convention.
After this we add the TranslateAccelerator function to the message loop, so the command can be processed in the window procedure:
BOOL bRet;
while (bRet = GetMessage(&Msg, NULL, 0, 0) > 0)
{
if (bRet == -1)
{
// Error handling can be done here.
}
else if (!TranslateAccelerator(hwnd, hAccel, &Msg))
{
TranslateMessage(&Msg);
DispatchMessage(&Msg);
}
}
Then finally inside the Window procedure
We add the code as follows:
switch(msg)
{
case WM_COMMAND:
{
switch (LOWORD(wParam))
{
case ID_SELECT_ALL:
{
HWND hEdit;
hEdit = GetDlgItem(hwnd, IDC_MAIN_EDIT) // Define IDC_MAIN_EDIT with an integer value in "Resource.h".
}
break;
}
break;
}
}
Note: The message passed to WM_COMMAND is the ID we defined for the ctrl+a accel.
I hope this will help fellow n00bies.