我正在使用iTextSharp v.4合并一大堆html文件。在我需要升级到iTextSharp的v.5之前，它一直运行良好。
当我将流读取器(读取html文件的内容)传递到HTMLWorker对象的ParseToList方法时，就会出现问题。它引发一个空引用异常。在调试它时，我可以访问streamReader并可以确认已读取文件的正确内容。
这是代码:
List<IElement> objects;
try
{
objects = HTMLWorker.ParseToList(new StringReader(htmlString), null);
}
catch (Exception e)
{
htmlString = "<html><head></head><body><br/><br/><h2 style='color:#FF0000'>ERROR READING FILE!</h2><h3>File Excluded From Stitched Document!</h3><br/><br/><p>There was an error while trying to read the following file:</p><p><span style='color:#FF0000'>" + fileName + "</span></p></body></html>";
objects = HTMLWorker.ParseToList(new StringReader(htmlString), null);
}
在catch块中，您将看到我然后实际上使用相同的代码将文本添加到pdf中，以表示存在问题。此代码可以正常工作。当然，这使我认为问题出在原始html字符串的内容中，因此这是字符串的内容，因为它就在传递到解析器之前:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<meta http-equiv="Pragma" content="no-cache" />
<meta http-equiv="cache-control" content="no-cache" />
</head>
<body style="font-family: Arial, Helvetica, sans-serif; font-size: 1em; margin: 0;
padding: 0;">
<div style="font-size: 1em; line-height: 1.25em; width: 190mm;">
<h1 style="font-size: 1.5em; font-weight: bold; margin: 0 0 1.5em 0; text-align: center;">
Advice Item 1</h1>
<table border="0" style="width: 190mm; border-collapse: collapse; margin: 0 0 1.5em 0;
width: 100%;">
<tbody>
<tr>
<td style="width: 35mm; height: 1px; line-height: 1px; font-size: 1px;">
</td>
<td>
</td>
<td style="width: 30mm; height: 1px; line-height: 1px; font-size: 1px;">
</td>
<td>
</td>
</tr>
<tr>
<td colspan="4" style="font-weight: bold;">
<span id="litPatchedToCC" style="text-align: right; font-weight: bold;"></span>
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
By:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
ABC
</td>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
From:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
CC
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Date:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
29/03/2011 13:35
</td>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
To:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
Member Practice
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Folder:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
A15-123456
</td>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Individual:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
Miss A B Test
</td>
</tr>
<tr>
<td colspan="2">
<hr width="100%" />
</td>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Of:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
Lorem & Ipsum
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Species:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
Bovine
</td>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Position:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
Member
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Item Type:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
</td>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Tel:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
0123 01234
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
</th>
<td style="font-weight: bold; padding: 2px 5px;">
</td>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Other Nos:
</th>
<td style="font-weight: bold; padding: 2px 5px;">
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Reason For Call:
</th>
<td colspan="3" style="font-weight: bold; padding: 2px 5px;">
Some Reason
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
Subject:
</th>
<td colspan="3" style="font-weight: bold; padding: 2px 5px;">
Some problem.
</td>
</tr>
<tr>
<th scope="row" style="text-align: right; font-weight: normal; padding: 2px 5px;">
</th>
<td>
</td>
<th scope="row" colspan="2" style="text-align: right; font-weight: normal; padding: 2px 5px;">
</th>
<td colspan="2">
</td>
</tr>
<tr>
<td style="font-size: 1.5em; font-weight: bold; text-align: center;" colspan="4">
Internal
</td>
</tr>
<tr>
<td colspan="4" style="text-align: center; padding: 2px 5px;">
<hr width="100%" />
</td>
</tr>
</tbody>
</table>
<div style="padding: 2px 5px;">
<p>
Here we start the discussion.</p>
<br />
<p>
Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p>
<br />
<p>
Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p>
</div>
</div>
</body>
</html>
谢谢你的帮助。
霍法纳威利
最佳答案
看来HTMLWorker在这两个<hr width="100%" />上令人窒息。由于您说过要升级到V5.XX，因此开始使用XMLWorker开始解析HTML也可能会很好-开发团队建议您使用它。 (最新的HTMLWorker源代码甚至有一个小引用指出了这一点)
经过扩展HTML的测试，它可以工作，并且实现起来还不错:)
using (Document document = new Document()) {
PdfWriter writer = PdfWriter.GetInstance(document, Response.OutputStream);
document.Open();
try {
StringReader sr = new StringReader(htmlString);
XMLWorkerHelper.GetInstance().ParseXHtml(
writer, document, sr
);
}
catch (Exception e) {
throw;
}
}
在网络环境中进行了测试，因此将
Response.OutputStream替换为您选择的Stream。