C#实现自动化PDF页码插入的示例代码

// 通过NuGet安装：Install-Package Spire.PDF
// 或在项目文件中添加：
// <PackageReference Include="Spire.PDF" Version="X.X.X" />

using Spire.Pdf;
using Spire.Pdf.Graphics;
using System.Drawing;

public class PdfPageNumberInserter
{
    public static void InsertSimplePageNumbers(string inputFilePath, string outputFilePath)
    {
        // 加载现有PDF文档
        PdfDocument doc = new PdfDocument();
        doc.LoadFromFile(inputFilePath);

        // 获取页面数量
        int pageCount = doc.Pages.Count;

        // 遍历每一页
        for (int i = 0; i < pageCount; i++)
        {
            PdfPageBase page = doc.Pages[i];

            // 创建字体和画刷
            PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("宋体", 10f, FontStyle.Regular), true);
            PdfBrush brush = PdfBrushes.Black;

            // 构建页码文本，例如 "第1页"
            string pageNumberText = $"第{i + 1}页";

            // 计算文本的宽度和高度
            SizeF textSize = font.MeasureString(pageNumberText);

            // 计算页码的绘制位置 (底部居中)
            float x = (page.Canvas.ClientSize.Width - textSize.Width) / 2;
            float y = page.Canvas.ClientSize.Height - textSize.Height - 10; // 距离底部10个点

            // 在页面上绘制页码
            page.Canvas.DrawString(pageNumberText, font, brush, x, y);
        }

        // 保存修改后的PDF文档
        doc.SaveToFile(outputFilePath);
        doc.Close();
    }
    static void Main(string[] args)
    {
        InsertSimplePageNumbers("Sample.pdf", "AddPageNumber.pdf");
    }
}

// 在循环内部修改页码文本构建逻辑
// 例如："第X页，共Y页"
string pageNumberText = $"第{i + 1}页，共{pageCount}页";

// 例如："Page X of Y"
// string pageNumberText = $"Page {i + 1} of {pageCount}";

public static void InsertRightAlignedPageNumbers(string inputFilePath, string outputFilePath)
{
    PdfDocument doc = new PdfDocument();
    doc.LoadFromFile(inputFilePath);
    int pageCount = doc.Pages.Count;

    for (int i = 0; i < pageCount; i++)
    {
        PdfPageBase page = doc.Pages[i];
        PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 10f, FontStyle.Regular), true);
        PdfBrush brush = PdfBrushes.Black;

        string pageNumberText = $"Page {i + 1} of {pageCount}";
        SizeF textSize = font.MeasureString(pageNumberText);

        // 页脚右侧对齐
        float x = page.Canvas.ClientSize.Width - textSize.Width - 20; // 距离右边缘20个点
        float y = page.Canvas.ClientSize.Height - textSize.Height - 20; // 距离底部20个点

        page.Canvas.DrawString(pageNumberText, font, brush, x, y);
    }
    doc.SaveToFile(outputFilePath);
    doc.Close();
}

public static void InsertPageNumbersExcludingFirstPage(string inputFilePath, string outputFilePath)
{
    PdfDocument doc = new PdfDocument();
    doc.LoadFromFile(inputFilePath);
    int pageCount = doc.Pages.Count;

    for (int i = 0; i < pageCount; i++)
    {
        // 排除第一页 (索引为0)
        if (i == 0) continue; 

        PdfPageBase page = doc.Pages[i];
        PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 10f, FontStyle.Regular), true);
        PdfBrush brush = PdfBrushes.Black;

        // 页码从1开始，但实际是文档的第2页
        string pageNumberText = $"Page {i} of {pageCount - 1}"; // 如果总页数也减去首页，则用pageCount-1

        SizeF textSize = font.MeasureString(pageNumberText);
        float x = page.Canvas.ClientSize.Width - textSize.Width - 20;
        float y = page.Canvas.ClientSize.Height - textSize.Height - 20;

        page.Canvas.DrawString(pageNumberText, font, brush, x, y);
    }
    doc.SaveToFile(outputFilePath);
    doc.Close();
}

// 字体：Arial, 12号字, 加粗斜体
PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 12f, FontStyle.Bold | FontStyle.Italic), true);

// 颜色：深蓝色
PdfBrush brush = new PdfSolidBrush(Color.DarkBlue);

// 绘制页码
page.Canvas.DrawString(pageNumberText, font, brush, x, y);

public static void InsertComplexFooter(string inputFilePath, string outputFilePath)
{
    PdfDocument doc = new PdfDocument();
    doc.LoadFromFile(inputFilePath);
    int pageCount = doc.Pages.Count;

    for (int i = 0; i < pageCount; i++)
    {
        PdfPageBase page = doc.Pages[i];
        PdfGraphics graphics = page.Canvas;

        // 页码字体和画刷
        PdfTrueTypeFont pageNumFont = new PdfTrueTypeFont(new Font("Arial", 9f, FontStyle.Italic), true);
        PdfBrush pageNumBrush = PdfBrushes.Gray;
        string pageNumberText = $"Page {i + 1} of {pageCount}";
        SizeF pageNumSize = pageNumFont.MeasureString(pageNumberText);

        // 其他页脚文本
        PdfTrueTypeFont footerFont = new PdfTrueTypeFont(new Font("Verdana", 8f, FontStyle.Regular), true);
        PdfBrush footerBrush = PdfBrushes.DarkGray;
        string footerText = "Generated by C# PDF Automation Tool";
        SizeF footerTextSize = footerFont.MeasureString(footerText);

        // 绘制页码 (右下角)
        float pageNumX = graphics.ClientSize.Width - pageNumSize.Width - 20;
        float pageNumY = graphics.ClientSize.Height - pageNumSize.Height - 15;
        graphics.DrawString(pageNumberText, pageNumFont, pageNumBrush, pageNumX, pageNumY);

        // 绘制其他页脚文本 (左下角)
        float footerTextX = 20;
        float footerTextY = graphics.ClientSize.Height - footerTextSize.Height - 15;
        graphics.DrawString(footerText, footerFont, footerBrush, footerTextX, footerTextY);

        // 绘制一条分隔线
        PdfPen linePen = new PdfPen(PdfBrushes.LightGray, 0.5f);
        graphics.DrawLine(linePen, 20, footerTextY - 5, graphics.ClientSize.Width - 20, footerTextY - 5);
    }
    doc.SaveToFile(outputFilePath);
    doc.Close();
}

try
{
    // ... PDF处理代码 ...
    InsertSimplePageNumbers("input.pdf", "output.pdf");
}
catch (FileNotFoundException ex)
{
    Console.WriteLine($"错误：文件未找到。{ex.Message}");
}
catch (PdfException ex)
{
    Console.WriteLine($"PDF处理错误：{ex.Message}");
}
catch (Exception ex)
{
    Console.WriteLine($"发生未知错误：{ex.Message}");
}