如何在C#中以程式化方式讀取PDF表單字段

using IronPdf;

// Load the source PDF
PdfDocument pdf = PdfDocument.FromFile("multipage-document.pdf");

// Convert to multipage TIFF with default settings
pdf.ToMultiPageTiffImage("multipage.tiff");

// Convert with custom DPI for better quality
pdf.ToMultiPageTiffImage("high-quality-multipage.tiff", 200);

// Convert specific page range to multipage TIFF
var pageRange = pdf.CopyPages(0, 9); // First 10 pages
pageRange.ToMultiPageTiffImage("range-multipage.tiff");

Imports IronPdf

' Load the source PDF
Dim pdf As PdfDocument = PdfDocument.FromFile("multipage-document.pdf")

' Convert to multipage TIFF with default settings
pdf.ToMultiPageTiffImage("multipage.tiff")

' Convert with custom DPI for better quality
pdf.ToMultiPageTiffImage("high-quality-multipage.tiff", 200)

' Convert specific page range to multipage TIFF
Dim pageRange = pdf.CopyPages(0, 9) ' First 10 pages
pageRange.ToMultiPageTiffImage("range-multipage.tiff")

Imports IronPdf

' Load PDF document
Dim pdf As PdfDocument = PdfDocument.FromFile("report.pdf")

' Convert to individual TIFF images
pdf.RasterizeToImageFiles("vb_output_*.tiff", ImageType.Tiff)

' Create multipage TIFF
pdf.ToMultiPageTiffImage("vb_multipage.tiff")

' Convert with custom DPI
pdf.ToTiffImages("vb_quality_*.tiff", 300)

' Process specific pages
Dim selectedPages = pdf.CopyPages(2, 5)
selectedPages.RasterizeToImageFiles("vb_selected_*.tiff", ImageType.Tiff)

using IronPdf;
using System.Linq;

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

// Extract first page as TIFF
PdfDocument firstPage = pdf.CopyPage(0);
firstPage.RasterizeToImageFiles("first_page.tiff", IronPdf.Imaging.ImageType.Tiff);

// Convert pages 5-10 to TIFF images
var pageRange = pdf.CopyPages(4, 9); // Zero-based indexing
pageRange.RasterizeToImageFiles("range_*.tiff", IronPdf.Imaging.ImageType.Tiff);

// Convert odd pages only
var oddPages = Enumerable.Range(0, pdf.PageCount)
    .Where(i => i % 2 == 0)
    .ToArray();
pdf.RasterizeToImageFiles("odd_*.tiff", oddPages, IronPdf.Imaging.ImageType.Tiff);

Imports IronPdf
Imports System.Linq

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

' Extract first page as TIFF
Dim firstPage As PdfDocument = pdf.CopyPage(0)
firstPage.RasterizeToImageFiles("first_page.tiff", IronPdf.Imaging.ImageType.Tiff)

' Convert pages 5-10 to TIFF images
Dim pageRange As PdfDocument = pdf.CopyPages(4, 9) ' Zero-based indexing
pageRange.RasterizeToImageFiles("range_*.tiff", IronPdf.Imaging.ImageType.Tiff)

' Convert odd pages only
Dim oddPages As Integer() = Enumerable.Range(0, pdf.PageCount) _
    .Where(Function(i) i Mod 2 = 0) _
    .ToArray()
pdf.RasterizeToImageFiles("odd_*.tiff", oddPages, IronPdf.Imaging.ImageType.Tiff)

using IronPdf;
using System.IO;

// Use memory streams for better performance
byte[] pdfBytes = File.ReadAllBytes("large-document.pdf");
using (var ms = new MemoryStream(pdfBytes))
{
    PdfDocument pdf = PdfDocument.FromStream(ms);

    // Process in batches to manage memory
    int batchSize = 10;
    for (int i = 0; i < pdf.PageCount; i += batchSize)
    {
        int endPage = Math.Min(i + batchSize - 1, pdf.PageCount - 1);
        var batch = pdf.CopyPages(i, endPage);
        batch.RasterizeToImageFiles($"batch{i}_*.tiff", IronPdf.Imaging.ImageType.Tiff);
        batch.Dispose(); // Free memory after each batch
    }
}

Imports IronPdf
Imports System.IO

' Use memory streams for better performance
Dim pdfBytes As Byte() = File.ReadAllBytes("large-document.pdf")
Using ms As New MemoryStream(pdfBytes)
    Dim pdf As PdfDocument = PdfDocument.FromStream(ms)

    ' Process in batches to manage memory
    Dim batchSize As Integer = 10
    For i As Integer = 0 To pdf.PageCount - 1 Step batchSize
        Dim endPage As Integer = Math.Min(i + batchSize - 1, pdf.PageCount - 1)
        Dim batch = pdf.CopyPages(i, endPage)
        batch.RasterizeToImageFiles($"batch{i}_*.tiff", IronPdf.Imaging.ImageType.Tiff)
        batch.Dispose() ' Free memory after each batch
    Next
End Using

using IronPdf;

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

// Convert to different formats
pdf.RasterizeToImageFiles("output_*.png", IronPdf.Imaging.ImageType.Png);
pdf.RasterizeToImageFiles("output_*.jpg", IronPdf.Imaging.ImageType.Jpeg);
pdf.RasterizeToImageFiles("output_*.bmp", IronPdf.Imaging.ImageType.Bitmap);
pdf.RasterizeToImageFiles("output_*.gif", IronPdf.Imaging.ImageType.Gif);

// WebP for modern web applications
pdf.RasterizeToImageFiles("output_*.webp", IronPdf.Imaging.ImageType.Webp);

Imports IronPdf

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

' Convert to different formats
pdf.RasterizeToImageFiles("output_*.png", IronPdf.Imaging.ImageType.Png)
pdf.RasterizeToImageFiles("output_*.jpg", IronPdf.Imaging.ImageType.Jpeg)
pdf.RasterizeToImageFiles("output_*.bmp", IronPdf.Imaging.ImageType.Bitmap)
pdf.RasterizeToImageFiles("output_*.gif", IronPdf.Imaging.ImageType.Gif)

' WebP for modern web applications
pdf.RasterizeToImageFiles("output_*.webp", IronPdf.Imaging.ImageType.Webp)

using IronPdf;

// For SharePoint integration
PdfDocument pdf = PdfDocument.FromFile("contract.pdf");
pdf.MetaData.Title = "Contract_2024";
pdf.MetaData.Keywords = "legal,contract,2024";
pdf.ToMultiPageTiffImage("sharepoint_ready.tiff");

// For compliance and archival
var archivalOptions = new IronPdf.Imaging.ImageRenderOptions
{
    Dpi = 300,  // High quality for long-term storage
    ImageType = IronPdf.Imaging.ImageType.Tiff
};

Imports IronPdf

' For SharePoint integration
Dim pdf As PdfDocument = PdfDocument.FromFile("contract.pdf")
pdf.MetaData.Title = "Contract_2024"
pdf.MetaData.Keywords = "legal,contract,2024"
pdf.ToMultiPageTiffImage("sharepoint_ready.tiff")

' For compliance and archival
Dim archivalOptions As New IronPdf.Imaging.ImageRenderOptions With {
    .Dpi = 300,  ' High quality for long-term storage
    .ImageType = IronPdf.Imaging.ImageType.Tiff
}