PDF File Versions

Curtis Chau

已更新:六月 1, 2025

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如何更改 PDF 版本？

PDF 版本标签根据您创建 PDF 时使用的功能设置。

例如：

使用基本 PDF 没有使用高级功能时，可能是 1.4
添加一个高级功能，例如图层，意味着版本标签更新为 1.7
从 PDF 中移除图层将使版本标签改回 1.4

PDF 创建工具总是尝试使用最低的 PDF 版本以确保兼容性。

然而，一个可以用于通过 IronPDF 将 PDF 文件版本从 1.4 更改为 1.7 的技巧是使用 PdfDocument.Merge() 静态方法和 PdfDocument.RemovePage() 方法的结合。下面的代码片段演示了如何做到这一点：

using IronPdf;

var renderer = new ChromePdfRenderer();

// Render the initial PDF that needs its version changed.
var pdf1 = renderer.RenderHtmlAsPdf("<h1>Hello, this is the required PDF</h1>");

// Render a mock PDF to use with the Merge() method.
var pdf2 = renderer.RenderHtmlAsPdf("<h1>This is a mock PDF</h1>");

// Merge the two PDFs. This will update the version to 1.7 if new features from pdf2 are used.
var pdf3 = PdfDocument.Merge(pdf1, pdf2);

// Remove the page from the mock PDF, keeping only the original content.
var pdf4 = pdf3.RemovePage(1);

// Save the resulting PDF document. It should have a version updated to 1.7.
pdf4.SaveAs("anothermerged.pdf");

using IronPdf;

var renderer = new ChromePdfRenderer();

// Render the initial PDF that needs its version changed.
var pdf1 = renderer.RenderHtmlAsPdf("<h1>Hello, this is the required PDF</h1>");

// Render a mock PDF to use with the Merge() method.
var pdf2 = renderer.RenderHtmlAsPdf("<h1>This is a mock PDF</h1>");

// Merge the two PDFs. This will update the version to 1.7 if new features from pdf2 are used.
var pdf3 = PdfDocument.Merge(pdf1, pdf2);

// Remove the page from the mock PDF, keeping only the original content.
var pdf4 = pdf3.RemovePage(1);

// Save the resulting PDF document. It should have a version updated to 1.7.
pdf4.SaveAs("anothermerged.pdf");

Imports IronPdf

Private renderer = New ChromePdfRenderer()

' Render the initial PDF that needs its version changed.
Private pdf1 = renderer.RenderHtmlAsPdf("<h1>Hello, this is the required PDF</h1>")

' Render a mock PDF to use with the Merge() method.
Private pdf2 = renderer.RenderHtmlAsPdf("<h1>This is a mock PDF</h1>")

' Merge the two PDFs. This will update the version to 1.7 if new features from pdf2 are used.
Private pdf3 = PdfDocument.Merge(pdf1, pdf2)

' Remove the page from the mock PDF, keeping only the original content.
Private pdf4 = pdf3.RemovePage(1)

' Save the resulting PDF document. It should have a version updated to 1.7.
pdf4.SaveAs("anothermerged.pdf")

$vbLabelText $csharpLabel

您可以检查生成的 PDF 输出的 PDF 版本。

另一方面，您 也可以 手动在 PDF 中更改版本标签，例如从 1.4 到 2.0，但那只是一个标签，并不会以任何实质性方式改变 PDF 本身。