我是.NET開發人員,因此代碼在C#中.但是你應該能夠輕松翻譯以下內容.
iText是一個PDF優先的庫,[X] HTML解析非常復雜,因此在這方面并不完整.每當解析[X] HTML并且事情不按預期的方式進行特定標記時,您應遵循的基本步驟是：
>驗證XML Worker支持標記：Tags class.
>如果支持標記(在本例中為true),請查看默認實現.這里由the HorizontalRule class處理.但是,我們看到不支持您的用例,所以一種方法是使用該代碼作為藍圖. (如下所示)您還可以繼承特定的標記類并覆蓋End()方法as done here.無論哪種方式,您所做的只是實現自定義標記處理器.
>如果不支持該標記,則需要通過繼承AbstractTagProcessor來滾動自己的自定義標記處理器.
無論如何,這是一個讓你入門的簡單例子.首先,自定義標簽處理器：
public class CustomHorizontalRule : AbstractTagProcessor
{
public override IList Start(IWorkerContext ctx, Tag tag)
{
IList result;
LineSeparator lineSeparator;
var cssUtil = CssUtils.GetInstance();
try
{
IList list = new List();
HtmlPipelineContext htmlPipelineContext = this.GetHtmlPipelineContext(ctx);
Paragraph paragraph = new Paragraph();
IDictionary css = tag.CSS;
float baseValue = 12f;
if (css.ContainsKey("font-size"))
{
baseValue = cssUtil.ParsePxInCmMmPcToPt(css["font-size"]);
}
string text;
css.TryGetValue("margin-top", out text);
if (text == null) text = "0.5em";
string text2;
css.TryGetValue("margin-bottom", out text2);
if (text2 == null) text2 = "0.5em";
string border;
css.TryGetValue(CSS.Property.BORDER_BOTTOM_STYLE, out border);
lineSeparator = border != null && border == "dotted"
? new DottedLineSeparator()
: new LineSeparator();
var element = (LineSeparator)this.GetCssAppliers().Apply(
lineSeparator, tag, htmlPipelineContext
);
string color;
css.TryGetValue(CSS.Property.BORDER_BOTTOM_COLOR, out color);
if (color != null)
{
// WebColors deprecated, but docs don't state replacement
element.LineColor = WebColors.GetRGBColor(color);
}
paragraph.SpacingBefore += cssUtil.ParseValueToPt(text, baseValue);
paragraph.SpacingAfter += cssUtil.ParseValueToPt(text2, baseValue);
paragraph.Leading = 0f;
paragraph.Add(element);
list.Add(paragraph);
result = list;
}
catch (NoCustomContextException cause)
{
throw new RuntimeWorkerException(
LocaleMessages.GetInstance().GetMessage("customcontext.404"),
cause
);
}
return result;
}
}
大多數代碼直接取自現有的源代碼,但CSS.Property.BORDER_BOTTOM_STYLE和CSS.Property.BORDER_BOTTOM_COLOR的檢查除外,如果它們在< hr>中內聯,則設置邊框樣式和顏色.樣式屬性.
然后將上面的自定義標記處理器添加到XML Worker TagProcessorFactory：
using (var stream = new FileStream(OUTPUT_FILE, FileMode.Create))
{
using (var document = new Document())
{
var writer = PdfWriter.GetInstance(document, stream);
document.Open();
var tagProcessorFactory = Tags.GetHtmlTagProcessorFactory();
// custom tag processor above
tagProcessorFactory.AddProcessor(
new CustomHorizontalRule(),
new string[] { HTML.Tag.HR }
);
var htmlPipelineContext = new HtmlPipelineContext(null);
htmlPipelineContext.SetTagFactory(tagProcessorFactory);
var pdfWriterPipeline = new PdfWriterPipeline(document, writer);
var htmlPipeline = new HtmlPipeline(htmlPipelineContext, pdfWriterPipeline);
var cssResolver = XMLWorkerHelper.GetInstance().GetDefaultCssResolver(true);
var cssResolverPipeline = new CssResolverPipeline(
cssResolver, htmlPipeline
);
var worker = new XMLWorker(cssResolverPipeline, true);
var parser = new XMLParser(worker);
var xHtml = "
";
using (var stringReader = new StringReader(xHtml))
{
parser.Parse(stringReader);
}
}
}
有一點需要注意的是,即使我們使用的是速記邊框內聯樣式,iText的CSS解析器似乎也會在內部設置所有樣式.即,您可以使用四種速記樣式中的任何一種來檢查 – 我恰好使用了CSS.Property.BORDER_BOTTOM_STYLE和CSS.Property.BORDER_BOTTOM_COLOR.
結果PDF：
)
