Code does not get much simpler than this. I needed to test putting a large icon in a dialog.
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include \masm32\include64\masm64rt.inc
.data?
hInstance dq ?
hIcon dq ?
.code
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entry_point proc
mov hInstance, rv(GetModuleHandle,0)
; -------------------------------------------------------------
; set the icon loaded size here to match the original icon size
; -------------------------------------------------------------
mov hIcon, rv(LoadImage,hInstance,10,IMAGE_ICON,128,128,LR_DEFAULTCOLOR)
invoke DialogBoxParam,hInstance,100,0,ADDR main,hIcon ; create a modal dialog
invoke ExitProcess,0
ret
entry_point endp
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main proc hWin:QWORD,uMsg:QWORD,wParam:QWORD,lParam:QWORD
.switch uMsg
.case WM_INITDIALOG
; ------------------------------------------------------
; lParam is the icon handle passed from DialogBoxParam()
; ------------------------------------------------------
invoke SendMessage,hWin,WM_SETICON,1,lParam ; set the icon for the dialog
invoke SendMessage,rv(GetDlgItem,hWin,102), \ ; set the icon in the client area
STM_SETIMAGE,IMAGE_ICON,lParam
invoke SetWindowText,hWin,"Big Icon Demo"
.return TRUE
.case WM_COMMAND
.switch wParam
.case 101
jmp exit_dialog ; The EXIT button
.endsw
.case WM_CLOSE
exit_dialog:
invoke EndDialog,hWin,0 ; exit from system menu
.endsw
xor rax, rax
ret
main endp
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end