How to Extract Digital Signature Details from Completed PDF Forms
Question details
The user needs a method to export information indicating whether completed PDF forms contain digital signatures and to identify the signers for data compilation.
- Product
- PDF Editors
- Device & OS
- not provided
- Scenario
- Aggregating data from multiple completed and signed PDF forms into a centralized spreadsheet to track signature statuses and signer identities.
- Observed behavior
- The user requires a programmatic way to read the digital certificate properties and signature status of multiple PDF documents to automate the data extraction and export process.
Ensure that the PDF forms use valid certificate-based digital signatures rather than standard electronic image stamps, as only cryptographic digital certificates contain extractable signer metadata.
Extract Signature Details using JavaScript (SignatureInfo)
Use JavaScript to programmatically read and export the certificate-based signature properties from the PDF signature fields.
Certificate-based signature fields in PDF files can be accessed programmatically via JavaScript. Each field features a SignatureInfo() function that returns a comprehensive object containing detailed properties about the digital signature, including the signer's identity, timestamp, and certificate validity.
Open your advanced PDF editor and navigate to the built-in JavaScript console or the document-level script editor.
Use the getField() method within your script to target the specific digital signature field in your PDF form by utilizing its exact field name.
Execute the signatureInfo() function on the targeted field to retrieve the digital certificate details (e.g., var sigInfo = field.signatureInfo();).
Extract specific properties from the object, such as the signer's name and the signing date, and format this data so it can be exported as a CSV file for your spreadsheet.
Verify and Manage PDF Digital Signatures in WPS Office
While automated batch extraction requires customized JavaScript, you can easily view, verify, and manage individual digital signatures on PDF forms using WPS Office. It provides a comprehensive set of PDF security tools alongside robust Word, Excel, and PowerPoint editing capabilities.
- 1. Open the Signed PDF: Launch WPS Office and open your completed PDF form containing the digital signature.
- 2. Access the Protect Tab: Navigate to the 'Protect' tab on the top ribbon menu to access the document's security and signature tools.
- 3. Verify Signature Details: Click directly on the digital signature in the document or select 'Manage Signatures' to view the full details of the signer's identity and the certificate's validity status.
- 4. Track in WPS Spreadsheet: For manual tracking, open a new WPS Spreadsheet alongside your PDF and record the verified signature details for your records.
Frequently Asked Questions
What is the difference between an electronic signature and a digital signature in PDFs?
An electronic signature is typically just an image, drawing, or typed text representing a signature. A digital signature is highly secure and uses a cryptographic digital certificate to verify the signer's exact identity and ensure the document has not been altered since it was signed.
Can I export standard PDF form field data directly to Excel?
Yes, many PDF editors allow you to export general form data. You can typically do this by navigating to the Form menu and selecting 'Export Data', which will generate a CSV or XML file that can be easily opened in Microsoft Excel or WPS Spreadsheet.
Why is the SignatureInfo() JavaScript function returning empty or undefined?
This usually occurs if the targeted field is not a true certificate-based signature field, if the field is currently empty (has not been signed yet), or if the script execution is being blocked by the strict security settings of your PDF viewer.
