替换文本 - 外观

在现有 PDF 文件中替换文本

为了在现有 PDF 文件中替换文本，您需要创建一个 PdfContentEditor 类的对象，并使用 BindPdf 方法绑定输入 PDF 文件。之后，您需要调用 ReplaceText 方法。您需要使用 PdfContentEditor 类的 Save 方法保存更新后的 PDF 文件。以下代码片段向您展示如何在现有 PDF 文件中替换文本。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText01()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using (var editor = new Aspose.Pdf.Facades.PdfContentEditor())
    {
        // Bind PDF document
        editor.BindPdf(dataDir + "sample.pdf");
        editor.ReplaceText("Value", "Label");

        // Save PDF document
        editor.Save(dataDir + "PdfContentEditorDemo01_out.pdf");
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText01()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor Object
    using var editor = new Aspose.Pdf.Facades.PdfContentEditor();

    // Bind PDF document
    editor.BindPdf(dataDir + "sample.pdf");
    editor.ReplaceText("Value", "Label");

    // Save PDF document
    editor.Save(dataDir + "PdfContentEditorDemo01_out.pdf");
}

查看原始文档中的样子：

并查看替换文本后的结果：

在第二个示例中，您将看到除了替换文本外，您还可以增加或减少字体大小：

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText02()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using (var editor = new Aspose.Pdf.Facades.PdfContentEditor())
    {
        // Bind PDF document
        editor.BindPdf(dataDir + "sample.pdf");
        editor.ReplaceText("Value", "Label", 12);

        // Save PDF document
        editor.Save(dataDir + "PdfContentEditorDemo02_out.pdf");
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText02()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using var editor = new Aspose.Pdf.Facades.PdfContentEditor();

    // Bind PDF document
    editor.BindPdf(dataDir + "sample.pdf");
    editor.ReplaceText("Value", "Label", 12);

    // Save PDF document
    editor.Save(dataDir + "PdfContentEditorDemo02_out.pdf");
}

对于更高级的文本处理功能，我们将使用 TextState 方法。通过此方法，我们可以使文本变为粗体、斜体、彩色等。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText03()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using (var editor = new Aspose.Pdf.Facades.PdfContentEditor())
    {
        // Bind PDF document
        editor.BindPdf(dataDir + "sample.pdf");

        var textState = new Aspose.Pdf.Text.TextState
        {
            ForegroundColor = Aspose.Pdf.Color.Red,
            FontSize = 12,
        };

        editor.ReplaceText("Value", "Label", textState);

        // Save PDF document
        editor.Save(dataDir + "PdfContentEditorDemo03_out.pdf");
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText03()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using var editor = new Aspose.Pdf.Facades.PdfContentEditor();

    // Bind PDF document
    editor.BindPdf(dataDir + "sample.pdf");

    var textState = new Aspose.Pdf.Text.TextState
    {
        ForegroundColor = Aspose.Pdf.Color.Red,
        FontSize = 12,
    };

    editor.ReplaceText("Value", "Label", textState);

    // Save PDF document
    editor.Save(dataDir + "PdfContentEditorDemo03_out.pdf");
}

如果您需要替换文档中所有指定的文本，请使用以下代码片段。也就是说，文本的替换将在遇到指定替换的文本时发生，并且还会计算此类替换的数量。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText04()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using (var editor = new Aspose.Pdf.Facades.PdfContentEditor())
    {
        // Bind PDF document
        editor.BindPdf(dataDir + "sample.pdf");
        int count = 0;

        while (editor.ReplaceText("Value", "Label"))
        {
            count++;
        }

        Console.WriteLine($"{count} occurrences have been replaced.");

        // Save PDF document
        editor.Save(dataDir + "PdfContentEditorDemo04_out.pdf");
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText04()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using var editor = new Aspose.Pdf.Facades.PdfContentEditor();

    // Bind PDF document
    editor.BindPdf(dataDir + "sample.pdf");
    int count = 0;

    while (editor.ReplaceText("Value", "Label"))
    {
        count++;
    }

    Console.WriteLine($"{count} occurrences have been replaced.");

    // Save PDF document
    editor.Save(dataDir + "PdfContentEditorDemo04_out.pdf");
}

以下代码片段展示了如何在文档的特定页面上进行所有文本替换。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText05()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using (var editor = new Aspose.Pdf.Facades.PdfContentEditor())
    {
        // Bind PDF document
        editor.BindPdf(dataDir + "sample.pdf");
        int count = 0;

        while (editor.ReplaceText("9999", 2, "ABCDE"))
        {
            count++;
        }

        Console.WriteLine($"{count} occurrences have been replaced.");

        // Save PDF document
        editor.Save(dataDir + "PdfContentEditorDemo05_out.pdf");
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText05()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using var editor = new Aspose.Pdf.Facades.PdfContentEditor();

    // Bind PDF document
    editor.BindPdf(dataDir + "sample.pdf");
    int count = 0;

    while (editor.ReplaceText("9999", 2, "ABCDE"))
    {
        count++;
    }

    Console.WriteLine($"{count} occurrences have been replaced.");

    // Save PDF document
    editor.Save(dataDir + "PdfContentEditorDemo05_out.pdf");
}

在下一个代码片段中，我们将展示如何将给定的数字替换为我们需要的字母。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText06()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using (var editor = new Aspose.Pdf.Facades.PdfContentEditor
           {
               ReplaceTextStrategy = new Aspose.Pdf.Facades.ReplaceTextStrategy
               {
                   IsRegularExpressionUsed = true,
                   ReplaceScope = Aspose.Pdf.Facades.ReplaceTextStrategy.Scope.ReplaceAll
               }
           })
    {
        // Bind PDF document
        editor.BindPdf(dataDir + "sample.pdf");
        editor.ReplaceText("\\d{4}", "ABCDE");

        // Save PDF document
        editor.Save(dataDir + "PdfContentEditorDemo06_out.pdf");
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ReplaceText06()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Instantiate PdfContentEditor object
    using var editor = new Aspose.Pdf.Facades.PdfContentEditor
    {
        ReplaceTextStrategy = new Aspose.Pdf.Facades.ReplaceTextStrategy
        {
            IsRegularExpressionUsed = true,
            ReplaceScope = Aspose.Pdf.Facades.ReplaceTextStrategy.Scope.ReplaceAll
        }
    };

    // Bind PDF document
    editor.BindPdf(dataDir + "sample.pdf");
    editor.ReplaceText("\\d{4}", "ABCDE");

    // Save PDF document
    editor.Save(dataDir + "PdfContentEditorDemo06_out.pdf");
}