为什么我的PDF生成为空白？ [英] Why is my PDF being generated as blank?
问题描述
我正在使用ItextSharp和c＃，asp.net MVC来生成PDF报告。但是，当我生成报告时，PDF返回为空白（除了正常工作的标题）。我很乐意为您提供意见。
I am using ItextSharp and c#, asp.net MVC to generate a PDF report. However, when I generate the report the PDF comes back as blank (apart from a header which is working fine). I would love your input.
生成报告的代码如下：
using (var writer = PdfWriter.GetInstance(doc, ms))
{
// This sorts out the Header and Footer parts.
var headerFooter = new ReportHeaderFooter(reportsAccessor);
writer.PageEvent = headerFooter;
var rootPath = ConfigurationManager.AppSettings["SaveFileRootPath"];
string html = File.ReadAllText(rootPath + "/reports/report.html");
// Perform the parsing to PDF
doc.Open();
// The html needs to be sorted before this call.
StringReader sr = new StringReader(html);
XMLWorkerHelper.GetInstance().ParseXHtml(writer, doc, sr);
doc.Close();
writer.Close();
res = ms.ToArray();
}
我知道有很多隐藏的，但为了论证，一个例子是这个生成并放入StringReader的HTML在这里：
I know there is a lot hidden, but for arguments sake an example of the HTML that this generates and puts in the StringReader is here:
<table style="font-size:10pt">
<tr>
<td rowspan="4"> Address<br/> </td>
<td>Phone: phone</td>
</tr>
<tr>
<td>Fax: fax</td>
</tr>
<tr>
<td>Email: email@example.com</td>
</tr>
<tr>
<td>Website: example.com</td>
</tr>
<table>
<table style="font-size:10pt; width:100%">
<tr style="width:50%">
<td>Settlement: 30 days from invoice</td>
</tr>
<tr>
<td>Delivery Charge Notes: N/A</td>
</tr>
</table>
<p style="width:100%; font-size:10pt">
I love notes</p>
<table>
<tr style="font-weight:bold">
<td>Item</td>
<td>Item Code</td>
<td>Description</td>
<td>Unit Size</td>
<td>Units Per Outer</td>
<td>Units Per Pallet</td>
<td>Invoice Price Volume Breaks</td>
<td>Branding</td>
<td>Notes</td>
</tr>
</table>
但是，这个html会生成一个漂亮的空白PDF文件（不是我想要的）。我看不出这可能有什么问题，并且会喜欢两件事：
However, this html generates a nice blank PDF file (not what I want). I can't see what might be wrong with this and would love some input in to two things:
[1]为什么报告是空白的
[2]如果这是解析中的一个错误，为什么它没有出现错误而是一个空白报告（我可以设置一个设置或参数，它会抛出比空白报告更有用的错误吗？）
[1] Why the report is blank [2] If this is an error in the parsing, why it doesn't come up with an error and instead a blank report (is there a setting or argument I can set that will throw errors which are much more useful than blank reports?)
更新：
我添加了页眉/页脚的代码
UPDATE: I have added the code for the header/footer
public string HeaderTitle {get ;组; }
public IReportsAccessor ReportsAccessor {get;组; }
public ReportHeaderFooter（IReportsAccessor reportsAccessor）
{
this.ReportsAccessor = reportsAccessor;
}
public string HeaderTitle { get; set; } public IReportsAccessor ReportsAccessor { get; set; } public ReportHeaderFooter(IReportsAccessor reportsAccessor) { this.ReportsAccessor = reportsAccessor; }
public override void OnStartPage(PdfWriter writer, Document document)
{
base.OnStartPage(writer, document);
var rootPath = ConfigurationManager.AppSettings["SaveFileRootPath"];
GetReportImageResult imgInfo = ReportsAccessor.GetImage(4);
byte[] header_img = imgInfo.ReportImage;
string logoFn = rootPath + "/tmp/logo.png";
File.WriteAllBytes(logoFn, header_img);
string html = File.ReadAllText(rootPath + "/reports/report_header.html");
html = html.Replace("{{ title }}", HeaderTitle);
html = html.Replace("{{ logo_img }}", logoFn);
StringReader sr = new StringReader(html);
XMLWorkerHelper.GetInstance().ParseXHtml(writer, document, sr);
}
推荐答案
当我运行你的HTML时我的代码，我确实得到了一个例外，因为你的HTML中有一个偷偷摸摸的错误。第一个表没有结束标记：它表示< table> 而不是< / table> 。这很容易被忽视。您可以在此处找到更正的HTML： table10.html
When I run your HTML through my code, I do get an exception, because there's one sneaky error in your HTML. The first table doesn't have a closing tag: it says <table> instead of </table>. That's easily overlooked. You can find the corrected HTML here: table10.html
这就是生成的PDF的样子： html_table_10 .pdf
This is what the resulting PDF looks like: html_table_10.pdf
您的代码和我的代码之间的一个主要区别是，我使用了iText / XML Worker 5.5.6（Java）并且您使用了iTextSharp / XML Worker（C＃）。虽然Java iText和XML Worker与C＃iTextSharp和XML Worker保持同步（因此应具有相同的行为），但底层XML解析器是不同的。
One major difference between your code and mine, is that I used iText / XML Worker 5.5.6 (Java) and you used iTextSharp / XML Worker (C#). While the Java iText and XML Worker are kept in sync with the C# iTextSharp and XML Worker (and should therefore have identical behavior), the underlying XML parser is different.
I知道我们决定表现得像浏览器（*），默默地允许一些糟糕的HTML构造失败，但我对Java XML解析的经验是抛出异常。也许C＃XML解析没有。
I know that we decided to behave like browsers (*), silently allowing some bad HTML constructs to fail, but my experience with the Java XML parsing is that is throws exceptions. Maybe the C# XML parsing doesn't.
（*）我是iText Group的首席执行官，包括比利时，美国和新加坡的公司。
(*) I'm the CEO of the iText Group, consisting of companies in Belgium, the US and Singapore.
至于css resolver crying异常，我们将在下一个版本中将其删除：
As for the "css resolver crying" exception, we'll remove it in the next release:
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