如何在NSIS安装程序脚本中捕获没有gotos / labels的YESNOCANCEL

我想知道如何在NSIS安装程序脚本中使用YESNOCANCEL MessageBox和LogicLib.nsh中的IF逻辑,以避免使用标签和gotos.

有没有办法在某种变量中捕获MessageBox的结果？

此外,我知道有比NSIS更好的东西,但在这一点上使用其他东西不是可能的. =(

请注意以下代码中的{WHAT GOES HERE ??}.如果这只是一个If … Else ……它会正常工作.

谢谢您的帮助

${If} ${Cmd} `MessageBox MB_YESNOCANCEL|MB_ICONEXCLAMATION 
"PROGRAM X is already installed. Click YES to remove the installed version 
 found in C:\Program Files(x86). Click NO to skip uninstall and choose a 
 different install location (not recommended) or CANCEL to terminate
  the installer." IDYES`

    MessageBox MB_OK "Yes was clicked"
${ElseIf} {WHAT GOES HERE??}
    MessageBox MB_OK "No was clicked"
${Else}    
    MessageBox MB_OK "Cancel was clicked"
${EndIf}

更新：
我也找到了这个例子,但我不确定${||}是做什么的,或者它对我有什么帮助.

; ifcmd..||..| and if/unless cmd
  StrCpy $R2 ""
  ${IfCmd} MessageBox MB_YESNO "Please click Yes" IDYES ${||} StrCpy $R2 $R2A ${|}
  ${Unless} ${Cmd} `MessageBox MB_YESNO|MB_DEFBUTTON2 "Please click No" IDYES`
    StrCpy $R2 $R2B
  ${EndUnless}
  ${If} $R2 == "AB"
    DetailPrint "PASSED IfCmd/If Cmd test"
  ${Else}
    DetailPrint "FAILED IfCmd/If Cmd test"
  ${EndIf}

解决方法

${IfThen} $Instdir == $Temp ${|} MessageBox mb_ok "$$InstDir equals $$Temp" ${|}

这只是简写语法：

${If} $Instdir == $Temp 
    MessageBox mb_ok "$$InstDir equals $$Temp" 
${EndIf}

IfCmd宏在内部使用${IfThen} ${Cmd},${||}是一个黑客来结束由IfCmd启动的字符串引用,所以：

${IfCmd} MessageBox MB_YESNO "click yes" IDYES ${||} MessageBox mb_ok choice=IDYES ${|}

是简写：

${If} ${Cmd} 'MessageBox MB_YESNO "yes" IDYES' ;notice the quotes here
    MessageBox mb_ok choice=IDYES
${EndIf}

你甚至可以混合ifthen和标签,但这是丑陋的恕我直言：

StrCpy $0 "Cancel"
${IfCmd} MessageBox MB_YESNOCANCEL "Mr. Powers?" IDYES yes IDNO ${||} StrCpy $0 "NO?!" ${|}
MessageBox mb_iconstop $0 ;Cancel or NO
goto end
yes:
MessageBox mb_ok "Yeah baby yeah!"
end:

(最好只使用MessageBox for YESNOCANCEL和ABORTRETRYIGNORE,对于YESNO,OKCANCEL等,为两个选项执行不同的代码,使用${If} ${Cmd}’MessageBox ..’.. ${Else} .. ${EndIf}语法)

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