iTextSharp PdfStamper.PartialFormFlattening僅展平一些而不是全部的字段

Question

以下代碼正確地將值「foo」指定給指定字段，但該字段未被「展平」。我必須忽略一個步驟，但我不知道它是什麼。請指教。謝謝。

public byte[] FlattenSpecifiedFormFields(byte[] b, List<string> fieldNames2Flatten) 
    { 
     PdfReader reader = new PdfReader(b); 
     using (var ms = new MemoryStream()) 
     { 
      var stamper = new iTextSharp.text.pdf.PdfStamper(reader, ms);    
      foreach (string name in fieldNames2Flatten) 
      { 

       stamper.AcroFields.SetField(name, "foo"); 
       stamper.PartialFormFlattening(name); 
      } 

      stamper.Close(); 
      return ms.ToArray(); 
     }; 
    } 

Answer 1

即使當部分地展平的形式中，PdfStamperFormFlattening屬性必須被設置爲true。即：

var stamper = new PdfStamper(reader, ms); 
stamper.FormFlattening = true; 

foreach (string name in fieldNames2Flatten) 
{ 
    stamper.AcroFields.SetField(name, "foo"); 
    stamper.PartialFormFlattening(name); 
}