- Add a link to PDF with an external destination
- Add a link with an internal destination to PDF
- Add a note to PDF
- Add barcodes to PDF
- Add bookmarks to PDF
- Add footer to PDF
- Add simple html text to PDF
- Add hyperlink to PDF
- Add multiline text to a PDF document
- Add a rubber stamp annotation with a custom icon
- Add single-line text to PDF
- Add Stamp to PDF
- Add text field to PDF
- Add a Diagonal Watermark to PDF in C# - TallComponents - PDF Library
- Append two or more existing PDF files
- Change the color inside a PDF
- Change the formatting of a numeric field
- Change page orientation PDF
- Clip PDF page content in C#
- Convert PDF to plain text
- Convert SVG to PDF
- Create a text annotation in PDF with rich text
- Create formfields in PDF documents
- Create layers in PDF and draw on each layer
- Create a new digitally signed PDF document
- Create rectangles with rounded corners
- Create text with decorations
- How to create a tiling for shapes in PDF
- Crop content on a PDF page
- Determine the content bounding box
- Determine if a PDF only contains images
- Digitally sign a PDF form in C# or VB.NET
- Disable submit button after submitting
- How to downscale all images in a PDF
- Download and convert image to PDF
- How to downscale all images in a PDF
- Vector graphics in PDF
- How to embed files in a PDF document
- Embed TrueType font in PDF
- EMF to PDF as raster image - Code Sample C#
- EMF to PDF as vector image
- Export FDF from PDF form
- Extract embedded files from PDF
- Extract glyph boxes from PDF
- Extract glyphs and sort by reading order
- Extract graphics from PDF
- Extract images from PDF
- Fill in a PDF form using MVC
- Fill in a template PDF document
- Fill PDF form
- Fit image to PDF page
- Flatten Markup Annotation
- Flatten PDF form
- How to generate and export certificates
- How do I extract page destinations from bookmarks?
- Highlight fields in PDF
- How do I create graphics with Icc based colors
- How to add autosized text to PDF
- How to sign and verify updates to a PDF document
- Import FDF into PDF
- Merge PDF files in C# .NET
- How to mirror PDF pages and other shapes
- Layout text with MultilineTextShape
- Read and write meta data from PDF
- How to reduce PDF file size
- Remove graphics from PDF
- Remove PDF security settings
- Replace field with image
- Resize PDF pages
- Rotate a PDF page
- How to scale content of PDF
- Search text in PDF
- PDF Viewer Preferences
- Create a custom signature handler to sign and verify PDF documents
- Split PDF pages in C# and VB.NET
- TIFF to PDF C#
- Translate PDF page content
- Use multiple licenses
- Use TrueType font collections
- Verify a custom digital PDF signature
Read and write meta data from PDF
This article shows a sample for reading and writing meta data from PDF using C#.
What is meta data
Metadata is used for data about the document like author, creation date …. These are the PDF standard metadata. PDF also supports custom metadata. Custom metadata could hold any kind of information. For example tracking info for a business process that involves the document. Metadata consists of name-value pairs under a metadata schema. The values are of type string. This can be any kind of string, but when it is structured data, it is very common to use XML for it, where the metadata schema holds an url to the schema that describes the structure of the XML.
More info about metadata can be found:
How to read meta data
The structure for meta data in the PDF document is as follows:
- A Document has an attribute MetadataSchemas of type MetadataSchemaCollection.
- The MetadataSchemaCollection is a collection of type MetadataSchema.
- A MetadataSchema has attributes Prefix, NamespaceUri and Names.
- The MetadataSchema holds a collection of name – value pairs.
- The Names attribute contains all the names of name – value pairs that are associated to the MetadataSchema.
- With a name a corresponding value can be retrieved from the MetadataSchema.
C# code sample that reads all the meta data from a PDF document
using (FileStream inputStream = new FileStream(@"..\..\input.pdf", FileMode.Open, FileAccess.Read))
{
Document document = new Document(inputStream);
MetadataSchemaCollection metadataSchemas = document.MetadataSchemas;
Console.WriteLine($"MetadataSchemas.Count = {metadataSchemas.Count}");
foreach (MetadataSchema metadataSchema in metadataSchemas)
{
Console.WriteLine($"MetadataSchema: {metadataSchema.Prefix} --> {metadataSchema.NamespaceUri}");
foreach (string name in metadataSchema.Names)
{
string value = "unknown";
MetadataString metadataString = metadataSchema[name] as MetadataString;
if (null != metadataString)
{
value = metadataString.Value;
}
Console.WriteLine($" - name = '{name}' value = '{value}'");
}
}
}
How to write meta data
Now that you know how to read meta data from a PDF, this section will provide a code sample that shows how to write meta data to PDF
Sample custom metadata XML from DocuSign
<?xml version="1.0" encoding="UTF-8"?>
<DocuSignDocumentTemplate xmlns="http://www.docusign.net/API/3.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" canAddTabs="true">
<Header>
<Name>template</Name>
<Version>1.0</Version>
...
</Header>
<Document>
<Name>ADV_AGRMT_DOC_EX1</Name>
<Source requireInstanceDoc="true">C:\Documents and Settings\a331760\Desktop\ADV_AGRMT_DOC_EX1.pdf</Source>
<NumPages>1</NumPages>
<Size>21050</Size>
</Document>
<Recipients>
<Recipient>
...
<RoleName>ESIG_PRIMARY_OWNER</RoleName>
<RoutingOrder>1</RoutingOrder>
<Type>Signer</Type>
<RequireAccessCode>false</RequireAccessCode>
...
<Tabs>
<Tab>
<PageNumber>1</PageNumber>
<XPosition>88</XPosition>
<YPosition>492</YPosition>
<Type>SignHere</Type>
</Tab>
</Tabs>
</Recipient>
...
</Recipients>
</DocuSignDocumentTemplate>
C# sample that writes meta data to a PDF document
Document document = new Document();
document.Pages.Add(new Page(PageSize.A4));
MetadataSchema metadataSchema = document.MetadataSchemas.Add("tc", @"http://test.tallcomponents.com/testschema/");
metadataSchema.Add("Songwriter", "Johansson");
metadataSchema.Add("Songs", "<songs><song>Close to my soul</song><song>Winter is over</song></songs>");
using (FileStream outputStream = new FileStream(@"output.pdf", FileMode.Create, FileAccess.Write))
{
document.Write(outputStream);
}