PdfDocumentSigner.GetPdfPkcs7Signature(String) Method
Retrieves the PKCS#7 signature of the signature field.
Namespace: DevExpress.Pdf
Assembly: DevExpress.Docs.v24.2.dll
NuGet Package: DevExpress.Document.Processor
#Declaration
public PdfPkcs7Signature GetPdfPkcs7Signature(
string signatureFieldName
)
#Parameters
Name | Type | Description |
---|---|---|
signature |
String | The signed form field. |
#Returns
Type | Description |
---|---|
Pdf |
A Pdf |
#Remarks
Call the GetPdfPkcs7Signature
method to obtain information about the PKCS#7 signature of the specified signature field.
The code snippet below obtains the PKCS#7 signature from a PDF document saved to the stream. Once the signature is obtained, the code checks attributes such as the time of signing, the signer’s identity, and authenticity of the signature.
using DevExpress.Pdf;
// ...
using(PdfDocumentSigner documentSigner = new PdfDocumentSigner(stream))
// Obtain the PKCS#7 signature from the list of `PdfSignatureInfo` objects.
foreach(var signature in documentSigner.GetSignatureInfo()) {
var pkcs7 = documentSigner.GetPdfPkcs7Signature(signature.FieldName);
// Obtain the PKCS#7 signature certificate.
var certificate = pkcs7.GetSignatureCertificate();
// Check wheter the signature is valid.
bool isValid = pkcs7.VerifySignature();
// Verify the signature certificate info.
string issuerName = certificate.IssuerName.Name;
bool isCertificateValid = certificate.Verify();
// Verify the time of signing.
var timeStamp = pkcs7.GetTimeStampDate();
bool isTimeStampValid = pkcs7.VerifyTimeStamp();
}