在使用HTML页眉/页脚的InsertPdf后发生AccessViolationException
Curtis Chau
Updated: 2026年6月12日
在另一个文档的页面合并后调用AccessViolationException。 在Debug构建或附加调试器时不会发生此异常。
System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
at IronPdf.PdfDocument.AddHtmlHeadersAndFooters(...)Text
在Release构建中，.NET JIT优化器允许垃圾回收器在托管对象不再被托管代码引用时，在它们的词法作用域结束前回收托管对象。 传递给PdfDocument可以在IronPDF的本地Chrome层仍在读取时被回收。 随后的AddHtmlHeadersAndFooters调用会访问已释放的内存，从而产生访问冲突。
解决方案
选项1：在InsertPdf之前应用页眉和页脚（推荐）
重新排序操作，使页眉和页脚在插入任何页面之前写入到基础文档中：
var renderer = new ChromePdfRenderer();
renderer.RenderingOptions.HtmlHeader = new HtmlHeaderFooter
{
HtmlFragment = "<div style='text-align:right; font-size:10px'>Page {page} of {total-pages}</div>"
};
var basePdf = renderer.RenderHtmlAsPdf(baseHtml);
basePdf.AddHtmlHeadersAndFooters(renderer.RenderingOptions);
var supplementPdf = PdfDocument.FromFile("supplement.pdf");
basePdf.InsertPdf(supplementPdf, 0);
basePdf.SaveAs("output.pdf");Dim renderer As New ChromePdfRenderer()
renderer.RenderingOptions.HtmlHeader = New HtmlHeaderFooter With {
.HtmlFragment = "<div style='text-align:right; font-size:10px'>Page {page} of {total-pages}</div>"
}
Dim basePdf = renderer.RenderHtmlAsPdf(baseHtml)
basePdf.AddHtmlHeadersAndFooters(renderer.RenderingOptions)
Dim supplementPdf = PdfDocument.FromFile("supplement.pdf")
basePdf.InsertPdf(supplementPdf, 0)
basePdf.SaveAs("output.pdf")Dim renderer As New ChromePdfRenderer()
renderer.RenderingOptions.HtmlHeader = New HtmlHeaderFooter With {
.HtmlFragment = "<div style='text-align:right; font-size:10px'>Page {page} of {total-pages}</div>"
}
Dim basePdf = renderer.RenderHtmlAsPdf(baseHtml)
basePdf.AddHtmlHeadersAndFooters(renderer.RenderingOptions)
Dim supplementPdf = PdfDocument.FromFile("supplement.pdf")
basePdf.InsertPdf(supplementPdf, 0)
basePdf.SaveAs("output.pdf")选项2：使用GC.KeepAlive防止提前回收
如果操作顺序不能更改，则延长PdfDocument的托管生命周期：
var renderer = new ChromePdfRenderer();
renderer.RenderingOptions.HtmlHeader = new HtmlHeaderFooter
{
HtmlFragment = "<div style='text-align:right; font-size:10px'>Page {page} of {total-pages}</div>"
};
var basePdf = renderer.RenderHtmlAsPdf(baseHtml);
var supplementPdf = PdfDocument.FromFile("supplement.pdf");
basePdf.InsertPdf(supplementPdf, 0);
basePdf.AddHtmlHeadersAndFooters(renderer.RenderingOptions);
GC.KeepAlive(supplementPdf);
basePdf.SaveAs("output.pdf");var renderer = new ChromePdfRenderer();
renderer.RenderingOptions.HtmlHeader = new HtmlHeaderFooter
{
HtmlFragment = "<div style='text-align:right; font-size:10px'>Page {page} of {total-pages}</div>"
};
var basePdf = renderer.RenderHtmlAsPdf(baseHtml);
var supplementPdf = PdfDocument.FromFile("supplement.pdf");
basePdf.InsertPdf(supplementPdf, 0);
basePdf.AddHtmlHeadersAndFooters(renderer.RenderingOptions);
GC.KeepAlive(supplementPdf);
basePdf.SaveAs("output.pdf");Imports IronPdf
Dim renderer As New ChromePdfRenderer()
renderer.RenderingOptions.HtmlHeader = New HtmlHeaderFooter With {
.HtmlFragment = "<div style='text-align:right; font-size:10px'>Page {page} of {total-pages}</div>"
}
Dim basePdf = renderer.RenderHtmlAsPdf(baseHtml)
Dim supplementPdf = PdfDocument.FromFile("supplement.pdf")
basePdf.InsertPdf(supplementPdf, 0)
basePdf.AddHtmlHeadersAndFooters(renderer.RenderingOptions)
GC.KeepAlive(supplementPdf)
basePdf.SaveAs("output.pdf")Imports IronPdf
Dim renderer As New ChromePdfRenderer()
renderer.RenderingOptions.HtmlHeader = New HtmlHeaderFooter With {
.HtmlFragment = "<div style='text-align:right; font-size:10px'>Page {page} of {total-pages}</div>"
}
Dim basePdf = renderer.RenderHtmlAsPdf(baseHtml)
Dim supplementPdf = PdfDocument.FromFile("supplement.pdf")
basePdf.InsertPdf(supplementPdf, 0)
basePdf.AddHtmlHeadersAndFooters(renderer.RenderingOptions)
GC.KeepAlive(supplementPdf)
basePdf.SaveAs("output.pdf")在supplementPdf的回收。
Curtis Chau 拥有卡尔顿大学的计算机科学学士学位，专注于前端开发，精通 Node.js、TypeScript、JavaScript 和 React。他热衷于打造直观且美观的用户界面，喜欢使用现代框架并创建结构良好、视觉吸引力强的手册。
