System.Drawing.Image ImgPDF = System.Drawing.Image.FromStream(MS)上的错误发生.给出“参数无效”的错误.

我认为它是有效的,当图像是位图,但没有任何其他格式.

我有以下代码 – 对不起长度;

private void Form1_Load(object sender,EventArgs e)
    {
        FileStream fs = File.OpenRead(@"reader.pdf");
        byte[] data = new byte[fs.Length];
        fs.Read(data,(int)fs.Length);
 
        List<System.Drawing.Image> ImgList = new List<System.Drawing.Image>();
 
        iTextSharp.text.pdf.RandomAccessFileOrArray RAFObj = null;
        iTextSharp.text.pdf.PdfReader PDFReaderObj = null;
        iTextSharp.text.pdf.PdfObject PDFObj = null;
        iTextSharp.text.pdf.PdfStream PDFStremObj = null;
 
        try
        {
            RAFObj = new iTextSharp.text.pdf.RandomAccessFileOrArray(data);
            PDFReaderObj = new iTextSharp.text.pdf.PdfReader(RAFObj,null);
 
            for (int i = 0; i <= PDFReaderObj.XrefSize - 1; i++)
            {
                PDFObj = PDFReaderObj.GetPdfObject(i);
 
                if ((PDFObj != null) && PDFObj.IsStream())
                {
                    PDFStremObj = (iTextSharp.text.pdf.PdfStream)PDFObj;
                    iTextSharp.text.pdf.PdfObject subtype = PDFStremObj.Get(iTextSharp.text.pdf.PdfName.SUBTYPE);
 
                    if ((subtype != null) && subtype.ToString() == iTextSharp.text.pdf.PdfName.IMAGE.ToString())
                    {
                        byte[] bytes = iTextSharp.text.pdf.PdfReader.GetStreamBytesRaw((iTextSharp.text.pdf.PRStream)PDFStremObj);
 
                        if ((bytes != null))
                        {
                            try
                            {
                                System.IO.MemoryStream MS = new System.IO.MemoryStream(bytes);
 
                                MS.Position = 0;
                                System.Drawing.Image ImgPDF = System.Drawing.Image.FromStream(MS);
 
                                ImgList.Add(ImgPDF);
 
                            }
                            catch (Exception)
                            {
                            }
                        }
                    }
                }
            }
            PDFReaderObj.Close();
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
 
 
 
    } //Form1_Load