如何使用 IronPDF 在 C# 中压缩 PDF

using IronPdf;

PdfDocument pdf = PdfDocument.FromFile("table.pdf");

// Pass null quality to skip image compression and true to drop the structure
// tree, which is the bulk of the size in table-heavy Chrome-rendered PDFs
pdf.CompressAndSaveAs("compressedTable.pdf", null, true);

Imports IronPdf

Dim pdf As PdfDocument = PdfDocument.FromFile("table.pdf")

' Pass Nothing quality to skip image compression and True to drop the structure
' tree, which is the bulk of the size in table-heavy Chrome-rendered PDFs
pdf.CompressAndSaveAs("compressedTable.pdf", Nothing, True)

using IronPdf;

PdfDocument pdf = PdfDocument.FromFile("sample.pdf");

// Shrink both sources of bloat in one pass: re-encode images at quality 80
// and strip the structure tree (true) for the largest size reduction
pdf.CompressAndSaveAs("compressed.pdf", 80, true);

Imports IronPdf

Dim pdf As PdfDocument = PdfDocument.FromFile("sample.pdf")

' Shrink both sources of bloat in one pass: re-encode images at quality 80
' and strip the structure tree (True) for the largest size reduction
pdf.CompressAndSaveAs("compressed.pdf", 80, True)

using IronPdf;

var pdf = PdfDocument.FromFile("input.pdf");

// Web or email: strong size reduction
pdf.CompressAndSaveAs("compressed.pdf", new AdvancedCompressionOptions
{
    JpegQuality = 70,
    TargetImageDpi = 150,
    RemoveStructureTree = true
});

// Print quality: minimal quality loss
pdf.CompressAndSaveAs("print.pdf", new AdvancedCompressionOptions
{
    JpegQuality = 90,
    TargetImageDpi = 300
});

Imports IronPdf

Dim pdf = PdfDocument.FromFile("input.pdf")

' Web or email: strong size reduction
pdf.CompressAndSaveAs("compressed.pdf", New AdvancedCompressionOptions With {
    .JpegQuality = 70,
    .TargetImageDpi = 150,
    .RemoveStructureTree = True
})

' Print quality: minimal quality loss
pdf.CompressAndSaveAs("print.pdf", New AdvancedCompressionOptions With {
    .JpegQuality = 90,
    .TargetImageDpi = 300
})

using IronPdf;

PdfDocument pdf = PdfDocument.FromFile("sample.pdf");

// Return the compressed PDF as bytes so it can go straight into an HTTP
// response, a database varbinary column, or a queue message with no temp file
byte[] compressedBytes = pdf.CompressPdfToBytes();

File.WriteAllBytes("compressed.pdf", compressedBytes);

Imports IronPdf

Dim pdf As PdfDocument = PdfDocument.FromFile("sample.pdf")

' Return the compressed PDF as bytes so it can go straight into an HTTP
' response, a database varbinary column, or a queue message with no temp file
Dim compressedBytes As Byte() = pdf.CompressPdfToBytes()

File.WriteAllBytes("compressed.pdf", compressedBytes)

using IronPdf;
using System.IO;

PdfDocument pdf = PdfDocument.FromFile("sample.pdf");

// Stream output so the compressed bytes can be piped straight to an HTTP
// response or cloud upload without first buffering the whole file as byte[]
using Stream compressedStream = pdf.CompressPdfToStream();

// CompressPdfToStream returns a read-only Stream, so copy it to the destination
using FileStream fileStream = File.Create("compressed.pdf");
compressedStream.CopyTo(fileStream);

Imports IronPdf
Imports System.IO

Dim pdf As PdfDocument = PdfDocument.FromFile("sample.pdf")

' Stream output so the compressed bytes can be piped straight to an HTTP
' response or cloud upload without first buffering the whole file as byte()
Using compressedStream As Stream = pdf.CompressPdfToStream()
    ' CompressPdfToStream returns a read-only Stream, so copy it to the destination
    Using fileStream As FileStream = File.Create("compressed.pdf")
        compressedStream.CopyTo(fileStream)
    End Using
End Using