在 GetButtonID 函数中，当给出多个按钮事件处理程序时，它会在显示目录 MUI 页面对话框之前自动退出。但是，当只给出一个按钮事件处理程序时，目录页面显示没有任何问题。
!include "MUI2.nsh"
!define IDC_BUTTON_CDRIVEPATH 1200
!define IDC_BUTTON_DDRIVEPATH 1201
;---------------------------------------
;Name and file
Name Remove_ERROR
OutFile solve_error.exe
; -------------------------------
!define MUI_ICON "${NSISDIR}\Contrib\Graphics\Icons\setup.ico" ;
!define MUI_HEADERIMAGE
!define MUI_HEADERIMAGE_BITMAP "${NSISDIR}\Contrib\Graphics\Header\icon.bmp"
!define MUI_WELCOMEFINISHPAGE_BITMAP"${NSISDIR}\Contrib\Graphics\Wizard\img.bmp"
!define MUI_ABORTWARNING
!insertmacro MUI_PAGE_WELCOME
!insertmacro MUI_PAGE_LICENSE "${NSISDIR}\Docs\Modern UI\licensefile.txt"
!define MUI_PAGE_CUSTOMFUNCTION_SHOW GetButtonID ** <---in this function only one button event handler works, if two handlers are given , then installer crashes**
!insertmacro MUI_PAGE_DIRECTORY
!insertmacro MUI_PAGE_COMPONENTS
!insertmacro MUI_PAGE_INSTFILES
!insertmacro MUI_PAGE_FINISH
Function **CDRIVEPATH**
MessageBox MB_OK|MB_ICONEXCLAMATION "The Software will be installed in : C Drive"
FunctionEnd
Function **DDRIVEPATH**
MessageBox MB_OK|MB_ICONEXCLAMATION "The Software will be installed in : D Drive"
FunctionEnd
;--------------------------------
Function **GetButtonID**
GetFunctionAddress $R2 CDRIVEPATH
ButtonEvent::AddEventHandler ${IDC_BUTTON_CDRIVEPATH} $R2
;when this second button handler is given ,then installer autoexits as soon as it has to show the Directory MUI Page dialog:
GetFunctionAddress $R3 DDRIVEPATH
ButtonEvent::AddEventHandler ${IDC_BUTTON_DDRIVEPATH} $R3
FunctionEnd
;------------------------------------------------------------------
Section "INSTALL MAIN SOFTWARE"
SetOutPath $INSTDIR
File /r "myfolder\*.*"
SectionEnd
;------------------------------------------------------------------
