invocations = 0;

function CheckIfPrintRequested() {
  invocations++;
  if (invocations > 1) return;
  switch (dialogArguments.__IE_PrintType) {
    case "Prompt":
      if (printer.showPageSetupDialog()) PrintPrep();
      break;
    case "NoPrompt":
      PrintPrep();
      break;
    case "Preview":
    default:
      break;
  }
}

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