iText 7 从 Asp.Net WebApi 返回 Pdf

Question

所以我整天都在搜索这个，我只是不知道如何让它工作。基本上我想在我的 ASP.Net WebApi 中使用 iText 7 创建一个 PDF 服务器端。非常简单明了的 PDF 创建：

[HttpGet]
public HttpResponseMessage CreateLieferschein()
{
    MemoryStream stream = new MemoryStream();

    PdfWriter writer = new PdfWriter(stream);
    var pdf = new PdfDocument(writer);
    var document = new Document(pdf);
    document.Add(new Paragraph("Hello World!"));

 }

从这里开始，我不知道如何从控制器返回文件。我真的很感激任何帮助，因为我刚刚迷路了。

Answer 1

试试这个：

 [HttpGet]
public HttpResponseMessage CreateLieferschein()
{

    Document doc = new Document(iTextSharp.text.PageSize.LETTER, 10, 10, 42, 35);
    byte[] buffer;
  HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.BadRequest);
     using(MemoryStream stream = new MemoryStream())
     {
     using(PdfWriter wri = PdfWriter.GetInstance(doc, mem)) 
     {
           PdfWriter writer = new PdfWriter(stream);
        var pdf = new PdfDocument(writer);
        var document = new Document(pdf);
        document.Add(new Paragraph("Hello World!"));
     }
     buffer = stream.ToArray();
       var contentLength = buffer.Length;

      var statuscode = HttpStatusCode.OK;
        response = Request.CreateResponse(statuscode);
        response.Content = new StreamContent(new MemoryStream(buffer));
        response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/pdf");
        response.Content.Headers.ContentLength = contentLength;
        ContentDispositionHeaderValue contentDisposition = null;
        if (ContentDispositionHeaderValue.TryParse("inline; filename=" + document.Name + ".pdf", out contentDisposition)) {
            response.Content.Headers.ContentDisposition = contentDisposition;
        }
    } else {
        var statuscode = HttpStatusCode.NotFound;
        var message = String.Format("Unable to find file. file \"{0}\" may not exist.", docid);
        var responseData = responseDataFactory.CreateWithOnlyMetadata(statuscode, message);
        response = Request.CreateResponse((HttpStatusCode)responseData.meta.code, responseData);
    }

    return response;

     }

Answer 2

我还没有尝试过，只是徒手做的，所以请耐心等待，但我认为您可以了解这里发生了什么。

public HttpResponseMessage CreateLieferschein() {

  // Create the itext pdf
  MemoryStream stream = new MemoryStream();            
  PdfWriter writer    = new PdfWriter(stream);
  var pdf             = new PdfDocument(writer);
  var document        = new Document(pdf);
  document.Add(new Paragraph("Hello World!"));
  document.Close();  // don't forget to close or the doc will be corrupt! ;)

  // Load the mem stream into a StreamContent
  HttpResponseMessage httpResponseMessage = new HttpResponseMessage(HttpStatusCode.OK)
  {
    Content = new StreamContent(stream)
  };

  // Prep the response with headers, filenames, etc.
  httpResponseMessage.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
  {
    FileName = "WebApi2GeneratedFile.pdf"
  };

  httpResponseMessage.Content.Headers.ContentType = new MediaTypeHeaderValue("application/pdf");

  ResponseMessageResult responseMessageResult = ResponseMessage(httpResponseMessage);

  // Cross your fingers...
  return responseMessageResult;

}