Digitally Sign PDF Documents in .NET Apps using GcPdf PDF API Library
Switch from paper to an electronic format and enhance security within your PDF documents. Add digital signatures to ensure your documents are secure. Encrypted digital signatures secure PDF documents–making them difficult to reproduce or forge.
Ensure non-repudiation, verify and authenticate an author's signature. Allow users to prove authorship or the validity of a contract or document.
Timestamp and validate signatures of existing PDF documents. Timestamps are essential for keeping records of when information is exchanged, created, or deleted online. Validate a signature to prove the authenticity of the signature timestamp.
Incrementally update PDF documents and validate digital signatures with multiple signatures. Signature for the .NET API library allows you to add various types of signatures to supported file formats. Adjust the signature properties and appearance as needed.
Apply digital certificates to a PDF file with a signature line and retrieve additional information from the signature's binary data. Each time a document is signed using a certificate, a signed version of the updated PDF is saved with the original PDF. Each version is saved as append-only and the original cannot be modified. After a document is signed, you can display a list of the changes made to the document after the last version.
Fully customize the appearance of the digital signature. Apply background color, borders, captions, customize caption location, and full-text support on the signatures. Add text, graphics, images, or shapes to a digital signature. Specify the signer and location for a pop-up and field lock options for signatures.
Easily sign-off on purchase orders with click-to-sign signature fields. Automatically lock the document fields to prevent further changes.
Digitally approve financial documents, such as budgets, expenses, and cost analysis to maximize efficiency. Manage all your budgeting information in a central location with confidence.
Verify and sign employee data. Perfect for timesheets, payroll, administrative employee information, or reports.
Digitally approve accomplishments, goals, KPIs, or OKR with a modern solution that is easy to use, track, and update.
Digital timestamps mark a PDF signature with the time and date as proof of integrity. A timestamp shows that the contents of the document existed at a point in time and are unchanged.
Extract Certificate Details
Extract signature information to troubleshoot problems that may occur due to binding dates of the certificate.
Long-Term Validation Signatures
Add long-term validation enabled signatures to your documents. Certify a document to ensure that a signature is valid at the time of signing. Compliant with Cryptographic Message Syntax (CMS), the advanced format of the Public Key Infrastructure (PKI)
Add an image to represent the signature with minimum lines of code. Add signature captions relative to the image. Supports JPEG, PNG, BMP, TIFF, GIF, and EXIF images. Customize image resolutions and the EXIF profile of images or signatures.
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