iTextsharp和pdf操作的问题(Issues with iTextsharp and pdf manipulation)

 我正在获取一个pdf文档（无密码），该文档是从第三方软件生成的，其中包含javascript和一些可编辑字段。 如果我使用pdfReader类加载此pdf文档，则NumberOfPagesProperty始终为1，尽管pdf文档有17页。 奇怪的是，如果我之后保存了流，那么该文档有17页。 当我现在尝试打开文档时，Acrobat Reader会显示扩展功能警告，并且字段不再可填写（我没有展平文档）。 有人知道这个问题吗？ 
 
 背景信息：我的工作是删除javascript代码，填写一些字段，然后保存文档。 我正在使用iTextsharp版本5.5.3.0。 
 
 遗憾的是，我无法上传示例文件，因为其中包含一些可靠的数据。 
 
private byte[] GetDocumentData(string documentName)
{
    var document = String.Format("{0}{1}\\{2}.pdf", _component.OutputDirectory,     _component.OutputFileName.Replace(".xml", ".pdf"), documentName);

    if (File.Exists(document))
    {
        PdfReader.unethicalreading = true;

        using (var originalData = new MemoryStream(File.ReadAllBytes(document)))
        {
            using (var updatedData = new MemoryStream())
            {                      
                var pdfTool = new PdfInserter(originalData, updatedData) {FormFlattening = false};
                pdfTool.RemoveJavascript();
                pdfTool.Save();  

                return updatedData.ToArray();
            }
        }
    }

    return null;
}

//Old version that wasn't working
public PdfInserter(Stream pdfInputStream, Stream pdfOutputStream)
{
    _pdfInputStream = pdfInputStream;
    _pdfOutputStream = pdfOutputStream;
    _pdfReader = new PdfReader(_pdfInputStream);
    _pdfStamper = new PdfStamper(_pdfReader, _pdfOutputStream);
}

//Solution
public PdfInserter(Stream pdfInputStream, Stream pdfOutputStream, char pdfVersion = '\0', bool append = true)
{
    _pdfInputStream = pdfInputStream;
    _pdfOutputStream = pdfOutputStream;
    _pdfReader = new PdfReader(_pdfInputStream);
    _pdfStamper = new PdfStamper(_pdfReader, _pdfOutputStream, pdfVersion, append);
}

public void RemoveJavascript()
{
    for (int i = 0; i <= _pdfReader.XrefSize; i++)
    {
        PdfDictionary dictionary = _pdfReader.GetPdfObject(i) as PdfDictionary;

        if (dictionary != null)
        {
            dictionary.Remove(PdfName.AA);
            dictionary.Remove(PdfName.JS);
            dictionary.Remove(PdfName.JAVASCRIPT);
        }
    }
}

I am getting a pdf-document (no password) which is generated from a third party software with javascript and a few editable fields in it. If I load this pdf-document with the pdfReader class the NumberOfPagesProperty is always 1 although the pdf-document has 17 pages. Oddly enough the document has 17 pages if I save the stream afterwards. When I now try to open the document the Acrobat Reader shows an extended feature warning and the fields are not fillable anymore (I haven't flattened the document). Do anyone know about such a problem? 
 
Background Info: My job is to remove the javascript code, fill out some fields and save the document afterwards. I am using the iTextsharp version 5.5.3.0.
 
Unfortunately I can't upload a sample file because there are some confidental data in it.
 
private byte[] GetDocumentData(string documentName)
{
    var document = String.Format("{0}{1}\\{2}.pdf", _component.OutputDirectory,     _component.OutputFileName.Replace(".xml", ".pdf"), documentName);

    if (File.Exists(document))
    {
        PdfReader.unethicalreading = true;

        using (var originalData = new MemoryStream(File.ReadAllBytes(document)))
        {
            using (var updatedData = new MemoryStream())
            {                      
                var pdfTool = new PdfInserter(originalData, updatedData) {FormFlattening = false};
                pdfTool.RemoveJavascript();
                pdfTool.Save();  

                return updatedData.ToArray();
            }
        }
    }

    return null;
}

//Old version that wasn't working
public PdfInserter(Stream pdfInputStream, Stream pdfOutputStream)
{
    _pdfInputStream = pdfInputStream;
    _pdfOutputStream = pdfOutputStream;
    _pdfReader = new PdfReader(_pdfInputStream);
    _pdfStamper = new PdfStamper(_pdfReader, _pdfOutputStream);
}

//Solution
public PdfInserter(Stream pdfInputStream, Stream pdfOutputStream, char pdfVersion = '\0', bool append = true)
{
    _pdfInputStream = pdfInputStream;
    _pdfOutputStream = pdfOutputStream;
    _pdfReader = new PdfReader(_pdfInputStream);
    _pdfStamper = new PdfStamper(_pdfReader, _pdfOutputStream, pdfVersion, append);
}

public void RemoveJavascript()
{
    for (int i = 0; i <= _pdfReader.XrefSize; i++)
    {
        PdfDictionary dictionary = _pdfReader.GetPdfObject(i) as PdfDictionary;

        if (dictionary != null)
        {
            dictionary.Remove(PdfName.AA);
            dictionary.Remove(PdfName.JS);
            dictionary.Remove(PdfName.JAVASCRIPT);
        }
    }
}

原文：https://stackoverflow.com/questions/27359259