java - 使用 itext 将多文本添加到现有 pdf

Question

我已经存在pdf模板

现在我想向此文件添加一些文本，所以我这样做了:

 PdfReader reader = new PdfReader(path + PdfCreator.TEMPORARY);
 PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(path + PdfCreator.DEST));
 PdfContentByte canvasBookingDate = stamper.getOverContent(1);
 //add text "Hellow"
 canvasBookingDate.setFontAndSize(base, 9.5f);   
 canvasBookingDate.moveText(72f, 788f);
 canvasBookingDate.showText("Hello");
 canvasBookingDate.moveText(72f, 762f);
 //add text "How are you"
 canvasBookingDate.setFontAndSize(base, 9.5f);   
 canvasBookingDate.showText("How are you");
 canvasBookingDate.setTextRenderingMode(PdfContentByte.TEXT_RENDER_MODE_FILL_STROKE);

问题是，pdf 文件中只插入了“Hello”，而没有插入“How are you” 也许我错了什么？

我还使用单独的 PdfContentByte 对象来编写每个文本，但没有运气

PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(path + PdfCreator.DEST));
 PdfContentByte canvasBookingDate = stamper.getOverContent(1);
 //add text "Hellow"
 canvasBookingDate.setFontAndSize(base, 9.5f);   
 canvasBookingDate.moveText(72f, 788f);
 canvasBookingDate.showText("Hello");
 canvasBookingDate.moveText(72f, 762f);

 //add text "How are you"
 PdfContentByte canvasPlanName2 = stamper.getOverContent(1);
 canvasPlanName2.setFontAndSize(base, 9.5f);   
 canvasPlanName2.moveText(72f, 762f);
 canvasPlanName2.showText(entity.getPlanName());
 canvasPlanName2.setTextRenderingMode(PdfContentByte.TEXT_RENDER_MODE_FILL_STROKE);

Answer 1

The problem is that, only "Hello" was inserted to pdf file, "How are you" was not

您的观察不准确:插入了“你好吗”，只是远离页面! (从 adobe reader 中执行 CtrlA CtrlC 并将其粘贴到某个编辑器中，您会发现它就在那里。)

原因是您误解了 moveText 的工作原理。看一下它的 JavaDoc 文档:

/**
 * Moves to the start of the next line, offset from the start of the current line.
 *
 * @param       x           x-coordinate of the new current point
 * @param       y           y-coordinate of the new current point
 */
public void moveText(final float x, final float y)

因此，坐标是相对的，而不是绝对的!

所以你应该这样做

canvasBookingDate.beginText();
canvasBookingDate.setFontAndSize(base, 9.5f);   
canvasBookingDate.moveText(72f, 788f);
canvasBookingDate.showText("Hello");
canvasBookingDate.moveText(0f, -16f);
//add text "How are you"
canvasBookingDate.showText("How are you");
canvasBookingDate.endText();