Question

如何使用itext7在内存流而不是物理文件中创建PDF？我不知道如何在最新版本中做任何帮助？

我尝试了以下代码，但pdfSM未正确填充：

string filePath = "./abc.pdf";

MemoryStream pdfSM = new ByteArrayOutputStream();

PdfDocument doc = new PdfDocument(new PdfReader(filePath), new PdfWriter(pdfSM));
.......

doc.close();

以下完整的测试代码供您参考，它在将文件路径传递到PdfWriter时工作，但不适用于内存流：

    public static readonly String sourceFolder = "../../FormTest/";

    public static readonly String destinationFolder = "../../Output/";

    static void Main(string[] args)
    {

        String srcFilePattern = "I-983";
        String destPattern = "I-129_2014_";

        String src = sourceFolder + srcFilePattern + ".pdf";
        String dest = destinationFolder + destPattern + "_flattened.pdf";
        MemoryStream returnSM = new MemoryStream();

        PdfDocument doc = new PdfDocument(new PdfReader(src), new PdfWriter(returnSM));

        PdfAcroForm form = PdfAcroForm.GetAcroForm(doc, false);

        foreach (PdfFormField field in form.GetFormFields().Values) 
        {
            var fieldName = field.GetFieldName();
            var type = field.GetType();
            if (fieldName != null)
            {
                if (type.Name.Equals("PdfTextFormField"))
                {
                        field.SetValue("T");
                }
            }               
        }
        form.FlattenFields();         
        doc.Close();

    }

Answer 1

这适合我。

    public byte[] CreatePdf()
    {
        var stream = new MemoryStream();
        var writer = new PdfWriter(stream);
        var pdf = new PdfDocument(writer);
        var document = new Document(pdf);

        document.Add(new Paragraph("Hello world!"));
        document.Close();

        return stream.ToArray();
    }

Answer 2

iText7，C＃控制器

错误：

public ActionResult Report()
{
    //...
    doc1.Close();
    return File(memoryStream1, "application/pdf", "pdf_file_name.pdf");
}

工作：

public ActionResult Report()
{
    //...
    doc1.Close();
    byte[] byte1 = memoryStream1.ToArray();
    return File(byte1, "application/pdf", "pdf_file_name.pdf");
}

我不知道为什么...但是，它在起作用！

另一个：link

Answer 3

我需要同样的东西。像这样工作：

 string HtmlString = "<html><head></head><body>some content</body></html>";
 byte[] buffer;
 using (MemoryStream memStream = new MemoryStream())
 {
     ConverterProperties props = new ConverterProperties();

     PdfDocument pdfDoc = new PdfDocument(new PdfWriter(memStream));
     pdfDoc.SetDefaultPageSize(PageSize.LETTER);
     HtmlConverter.ConvertToPdf(HtmlString, pdfDoc, props);
     pdfDoc.Close();
     buffer = memStream.ToArray();
 }
 return buffer;

C＃8“使用”语句替代：

using MemoryStream memStream = new MemoryStream();
ConverterProperties props = new ConverterProperties();

PdfDocument pdfDoc = new PdfDocument(new PdfWriter(memStream));
pdfDoc.SetDefaultPageSize(PageSize.LETTER);
HtmlConverter.ConvertToPdf(reader, pdfDoc, props);
pdfDoc.Close();
buffer = memStream.ToArray();

iText7在内存中创建PDF而不是物理文件

3 个答案: