如果我使用字体大小出现. setLayer2FontSize（6.0f）；它为名称和描述设置字体大小。
PdfReader reader = null;
PdfSigner signer = null;
try {
reader = new PdfReader(inStream);
signer = new PdfSigner(reader, pdfos, false);
} catch (IOException e) {
LOGGER.error("Error while loading PDF");
throw new DigitalSignException("Error while loading PDF", e);
}
int noOfPages = signer.getDocument().getNumberOfPages();
PdfSignatureAppearance appearance = signer.getSignatureAppearance().setReason(reason).setLocation(loc)
.setReuseAppearance(false);
Rectangle rect = new Rectangle(250, 100, 200, 80);
appearance.setRenderingMode(RenderingMode.NAME_AND_DESCRIPTION);
appearance.setLayer2FontSize(6.0f);
appearance.setPageRect(rect).setPageNumber(noOfPages);
signer.setFieldName("sign");
// Creating the signature
IExternalSignature pks = new PrivateKeySignature(pk, digestAlgorithm, bouncyCastleProvider.getName());
IExternalDigest digest = new BouncyCastleDigest();
try {
signer.signDetached(digest, pks, chain, null, null, null, 0, subfilter);
} catch (IOException | GeneralSecurityException e) {
LOGGER.error("Error while adding digital signature to PDF");
throw new DigitalSignException("Error while adding digital signature to PDF", e);
}
有没有办法为名称和描述设置不同的字体大小（名称应该比描述大一点）
整个Layer2Text是一个单一的String，无论你是设置它还是iText构建它，它都是使用单一字体和字体大小排版为单个段落。因此，不，你不能要求iText为它的不同部分使用多种样式来绘制你的Layer2Text或它的默认文本。
但是，您可以做的是在iText在其上创建外观之前检索PdfFormXObjectLayer2，并且您可以在其上绘制任何样式的任何内容。
所以，与其
appearance.setRenderingMode(RenderingMode.NAME_AND_DESCRIPTION);
appearance.setLayer2FontSize(6.0f);
appearance.setPageRect(rect).setPageNumber(noOfPages);
你会做
appearance.setPageRect(rect).setPageNumber(noOfPages);
PdfFormXObject layer2 = getLayer2();
[...shape the layer2 contents as you desire...]
当然，您可以使用PdfSignature外观方法get外观的源代码来获取灵感，特别是如果您不希望您的设计与默认值偏离太多。
因此，是的，您可以完全自定义签名外观。
一个示例自定义的layer2内容可能如下所示：
PdfFormXObject layer2 = appearance.getLayer2();
PdfCanvas canvas = new PdfCanvas(layer2, signer.getDocument());
float MARGIN = 2;
PdfFont font = PdfFontFactory.createFont();
String name = null;
CertificateInfo.X500Name x500name = CertificateInfo.getSubjectFields((X509Certificate)chain[0]);
if (x500name != null) {
name = x500name.getField("CN");
if (name == null)
name = x500name.getField("E");
}
if (name == null)
name = "";
Rectangle dataRect = new Rectangle(rect.getWidth() / 2 + MARGIN / 2, MARGIN, rect.getWidth() / 2 - MARGIN, rect.getHeight() - 2 * MARGIN);
Rectangle signatureRect = new Rectangle(MARGIN, MARGIN, rect.getWidth() / 2 - 2 * MARGIN, rect.getHeight() - 2 * MARGIN);
try (Canvas layoutCanvas = new Canvas(canvas, signer.getDocument(), signatureRect);) {
Paragraph paragraph = new Paragraph(name).setFont(font).setMargin(0).setMultipliedLeading(0.9f).setFontSize(20);
layoutCanvas.add(paragraph);
}
try (Canvas layoutCanvas = new Canvas(canvas, signer.getDocument(), dataRect);) {
Paragraph paragraph = new Paragraph().setFont(font).setMargin(0).setMultipliedLeading(0.9f);
paragraph.add(new Text("Digitally signed by ").setFontSize(6));
paragraph.add(new Text(name + '\n').setFontSize(9));
paragraph.add(new Text("Date: " + new SimpleDateFormat("yyyy.MM.dd HH:mm:ss z").format(signer.getSignDate().getTime()) + '\n').setFontSize(6));
paragraph.add(new Text("Reason: " + appearance.getReason() + '\n').setFontSize(6));
paragraph.add(new Text("Location: " + appearance.getLocation()).setFontSize(6));
layoutCanvas.add(paragraph);
}
这本质上是一个复制品
