禁用下一步按钮，直到nsDialogs填满为止

!include nsDialogs.nsh

Var dialog
Var nextButton

Function onInit
  StrCpy $dialog 0
  StrCpy $nextButton 0
FunctionEnd

Function pageCallback
  ${NSD_GetText} $0 $dialog
  ${NSD_GetState} $1 $nextButton

  ; 检查字段填写状态
  ${If} $0 == ""
    ; 字段未填写完整，禁用下一步按钮
    ${NSD_SetState} $1 1
  ${Else}
    ; 字段填写完整，启用下一步按钮
    ${NSD_SetState} $1 0

    ; 判断是否填满
    ${If} $dialog == "填满条件"
      ; 填满，可以进行下一步操作
      MessageBox MB_OK "可以进行下一步操作"
    ${EndIf}
  ${EndIf}
FunctionEnd

Page custom nsDialogsPageCreate nsDialogsPageLeave
Page instfiles

Function nsDialogsPageCreate
  nsDialogs::Create 1018
  Pop $dialog

  ${NSD_CreateText} 0 0 100% 12u ""
  Pop $0
  ${NSD_OnChange} $0 pageCallback

  ${NSD_CreateButton} 0 15u 100% 12u "下一步"
  Pop $nextButton
  ${NSD_OnClick} $nextButton pageCallback

  nsDialogs::Show
FunctionEnd

Function nsDialogsPageLeave
  nsDialogs::Destroy
FunctionEnd