如何用 C# 访问所有 PDF DOM 对象

using IronPdf;
using System.Linq;

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

var glyph = pdf.Pages.First().ObjectModel.TextObjects.First().GetGlyphInfo();

Imports IronPdf
Imports System.Linq

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

Dim glyph = pdf.Pages.First().ObjectModel.TextObjects.First().GetGlyphInfo()

using IronPdf;
using System.Drawing;
using System.Linq;

// Setup the Renderer
var renderer = new ChromePdfRenderer();

// We use CSS Flexbox to perfectly center the text vertically and horizontally.
var html = @"
<div style='display: flex; justify-content: center; align-items: center; font-size: 48px;'>
    Centered
</div>";

// Render the HTML to a PDF
PdfDocument pdf = renderer.RenderHtmlAsPdf(html);

// Save the original PDF to see the "before" state
pdf.SaveAs("BeforeTranslate.pdf");

// Access the first text object on the first page
// In this simple HTML, this will be our "Centered" text block.
var textObject = pdf.Pages.First().ObjectModel.TextObjects.First();

// Apply the translation
// This moves the object 200 points to the right and 150 points up from its original position.
textObject.Translate = new PointF(200, 150);

// Save the modified PDF to see the "after" state
pdf.SaveAs("AfterTranslate.pdf");

Imports IronPdf
Imports System.Drawing
Imports System.Linq

' Setup the Renderer
Dim renderer As New ChromePdfRenderer()

' We use CSS Flexbox to perfectly center the text vertically and horizontally.
Dim html As String = "
<div style='display: flex; justify-content: center; align-items: center; font-size: 48px;'>
    Centered
</div>"

' Render the HTML to a PDF
Dim pdf As PdfDocument = renderer.RenderHtmlAsPdf(html)

' Save the original PDF to see the "before" state
pdf.SaveAs("BeforeTranslate.pdf")

' Access the first text object on the first page
' In this simple HTML, this will be our "Centered" text block.
Dim textObject = pdf.Pages.First().ObjectModel.TextObjects.First()

' Apply the translation
' This moves the object 200 points to the right and 150 points up from its original position.
textObject.Translate = New PointF(200, 150)

' Save the modified PDF to see the "after" state
pdf.SaveAs("AfterTranslate.pdf")

using IronPdf;
using System.Linq;

// Setup the Renderer
var renderer = new ChromePdfRenderer();

// The image is placed in a div to give it some space on the page.
string html = @"<img src='https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTi8LuOR6_A98euPLs-JRwoLU7Nc31nVP15rw&s'>";

// Render the HTML to a PDF
PdfDocument pdf = renderer.RenderHtmlAsPdf(html);

// Save the PDF before scaling for comparison
pdf.SaveAs("BeforeScale.pdf");

// Access the first image object on the first page
var image = pdf.Pages.First().ObjectModel.ImageObjects.First();

// We scale the image to 70% of its original size on both the X and Y axes.
image.Scale = new System.Drawing.PointF(0.7f, 0.7f);

// Save the modified PDF to see the result
pdf.SaveAs("AfterScale.pdf");

Imports IronPdf
Imports System.Linq
Imports System.Drawing

' Setup the Renderer
Dim renderer As New ChromePdfRenderer()

' The image is placed in a div to give it some space on the page.
Dim html As String = "<img src='https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTi8LuOR6_A98euPLs-JRwoLU7Nc31nVP15rw&s'>"

' Render the HTML to a PDF
Dim pdf As PdfDocument = renderer.RenderHtmlAsPdf(html)

' Save the PDF before scaling for comparison
pdf.SaveAs("BeforeScale.pdf")

' Access the first image object on the first page
Dim image = pdf.Pages.First().ObjectModel.ImageObjects.First()

' We scale the image to 70% of its original size on both the X and Y axes.
image.Scale = New PointF(0.7F, 0.7F)

' Save the modified PDF to see the result
pdf.SaveAs("AfterScale.pdf")

using IronPdf;
using System.Linq;

// Load the PDF file we created in the Scale example
PdfDocument pdf = PdfDocument.FromFile("BeforeScale.pdf");

// Access DOM Objects
var objects = pdf.Pages.First().ObjectModel;

// Remove first image
objects.ImageObjects.RemoveAt(0);

// Save the modified PDF
pdf.SaveAs("removedFirstImage.pdf");

Imports IronPdf
Imports System.Linq

' Load the PDF file we created in the Scale example
Dim pdf As PdfDocument = PdfDocument.FromFile("BeforeScale.pdf")

' Access DOM Objects
Dim objects = pdf.Pages.First().ObjectModel

' Remove first image
objects.ImageObjects.RemoveAt(0)

' Save the modified PDF
pdf.SaveAs("removedFirstImage.pdf")

// Example of combining multiple DOM operations
using IronPdf;
using System.Linq;

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

// Iterate through all pages
foreach (var page in pdf.Pages)
{
    var objects = page.ObjectModel;

    // Process text objects
    foreach (var textObj in objects.TextObjects)
    {
        // Change color of specific text
        if (textObj.Contents.Contains("Important"))
        {
            textObj.Color = System.Drawing.Color.Red;
        }
    }

    // Scale down all images by 50%
    foreach (var imgObj in objects.ImageObjects)
    {
        imgObj.Scale = new System.Drawing.PointF(0.5f, 0.5f);
    }
}

pdf.SaveAs("processed-document.pdf");

Imports IronPdf
Imports System.Linq
Imports System.Drawing

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

' Iterate through all pages
For Each page In pdf.Pages
    Dim objects = page.ObjectModel

    ' Process text objects
    For Each textObj In objects.TextObjects
        ' Change color of specific text
        If textObj.Contents.Contains("Important") Then
            textObj.Color = Color.Red
        End If
    Next

    ' Scale down all images by 50%
    For Each imgObj In objects.ImageObjects
        imgObj.Scale = New PointF(0.5F, 0.5F)
    Next
Next

pdf.SaveAs("processed-document.pdf")