在iTextSharp中添加新行

Question

我一直试图解决这个问题一段时间后无济于事.我在iTextSharp中有一些文字我试图换一个换行符.我已经使用试图\n转义字符,Environment.NewLine以及document.Add(new Phrase(Environment.NewLine))没有任何成功.有没有办法做到这一点？这是我正在尝试执行此操作的代码段(注意注释的行//Doesn't work):

//Open the reader
PdfReader reader = new PdfReader(oldFile);
Rectangle size = reader.GetPageSizeWithRotation(1);
Document document = new Document(size);
// open the writer
FileStream fs = new FileStream(newFile, FileMode.Create, FileAccess.Write);
PdfWriter writer = PdfWriter.GetInstance(document, fs);
document.Open();

//Configure the content
PdfContentByte cb = writer.DirectContent;
// select the font properties
BaseFont bf = BaseFont.CreateFont("c:\\windows\\fonts\\calibri.ttf", BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
cb.SetColorFill(BaseColor.BLACK);
cb.SetFontAndSize(bf, 10);

//Write the text here
cb.BeginText();
text = "F\n";//Doesn’t work
document.Add(new Phrase(Environment.NewLine));//Doesn’t work
text += "o\n";
text += Environment.NewLine;//Doesn’t work
text += "o\n";
cb.ShowTextAligned(PdfContentByte.ALIGN_LEFT, text, 85, 311, 0);
cb.EndText();

//Create the new page
PdfImportedPage page = writer.GetImportedPage(reader, 1);
cb.AddTemplate(page, 0, 0);

//Close all streams
document.Close();
fs.Close();
writer.Close();
reader.Close();

有什么建议？

编辑一:

仍然没有合作document.Add(new Paragraph("\n"));.我做错了吗？

cb.BeginText();
text = "F";
document.Add(new Paragraph("\n"));
text += "o";
document.Add(new Paragraph("\n"));
text += "o";
cb.ShowTextAligned(PdfContentByte.ALIGN_LEFT, text, 85, 311, 0);
cb.EndText();

Answer 1

有两种主要的方法与iTextSharp的文字工作,或者通过类似的抽象Paragraph和Phrase或通过手动执行命令PdfContentByte.抽象将处理边距,换行符和间距等事情,而手动路线完全取决于您.你不能真正混合你正在做的两个.除非您特别需要粒度控制,否则我强烈建议使用抽象而不是手动路径.以下是显示两者的示例.

但要具体回答您的问题,原始PDF命令(您正在使用)x,y从左到右绘制某些坐标的文本,并且它们不支持"返回"或"换行符"的概念.为此,您需要手动将当前文本光标移动到新行.请参阅下面的代码以获取该示例.

        string outputFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "test.pdf");
        using (FileStream fs = new FileStream(outputFile, FileMode.Create, FileAccess.Write, FileShare.None)) {
            using (Document doc = new Document(PageSize.LETTER)) {
                using (PdfWriter writer = PdfWriter.GetInstance(doc, fs)) {
                    doc.Open();

                    //This creates two lines of text using the iTextSharp abstractions
                    doc.Add(new Paragraph("This is Paragraph 1"));
                    doc.Add(new Paragraph("This is Paragraph 2"));

                    //This does the same as above but line spacing needs to be calculated manually
                    PdfContentByte cb = writer.DirectContent;
                    cb.SaveState();
                    cb.SetColorFill(BaseColor.BLACK);
                    cb.SetFontAndSize(BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED), 12f);
                    cb.BeginText();
                    cb.ShowTextAligned(PdfContentByte.ALIGN_LEFT, "This is cb1", 20, 311, 0);
                    cb.ShowTextAligned(PdfContentByte.ALIGN_LEFT, "This is cb2", 20, 291, 0);//Just guessing that line two should be 20px down, will actually depend on the font
                    cb.EndText();
                    cb.RestoreState();
                    doc.Close();
                }
            }
        }

Answer 2

尝试这样的事情:

document.Add(new Chunk("\n"));

Answer 3

document.Add(new Paragraph(" "));适合我.请记住,该Paragraph语句会自动添加换行符.你所要做的就是给它渲染一些东西.在这种情况下,空间会很好.