PDF File Versions

Curtis Chau

更新日期:6月 1, 2025

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如何更改PDF版本？

PDF版本標籤是根據創建PDF時使用的功能設置的。

例如：

使用基本功能的PDF通常是1.4版本
添加進階功能（如圖層）後，版本標記會更新為1.7
從PDF中移除圖層將使版本標記變回1.4

PDF創建工具總是嘗試使用最低的PDF版本以確保兼容性。

然而，可以使用IronPDF中的PdfDocument.Merge()靜態方法和PdfDocument.RemovePage()方法的組合來將PDF檔版本從1.4更改至1.7。以下代碼片段展示了如何實現這一操作：

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

您可以檢查結果PDF輸出的PDF版本。

另一方面，您_還可以_手動更改PDF中的版本標記，例如從1.4更改為2.0，但這只是一個標籤，這種方式不會以任何有意義的方式改變PDF本身。