(C#) Create PKCS7 Signed File (.p7m)

Demonstrates how to sign a file to create a .p7m that contains both the file contents and the signature.

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// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Crypt2 crypt = new Chilkat.Crypt2();

Chilkat.CertStore certStore = new Chilkat.CertStore();

// Load a PFX file into a certificate store object.
bool success = certStore.LoadPfxFile("myPfx.pfx","pfxPassword");
if (success != true) {
    Debug.WriteLine(certStore.LastErrorText);
    return;
}

// Get the certificate by subject common name.
// This should be the cert within the PFX that also
// has a private key (also stored within the PFX).
Chilkat.Cert cert = certStore.FindCertBySubjectCN("myCert");
if (certStore.LastMethodSuccess == false) {
    Debug.WriteLine(certStore.LastErrorText);
    return;
}

// Tell the crypt object to use the certificate for signing:
success = crypt.SetSigningCert(cert);

// Sign a file, producing a .p7m as output.
// The input file is unchanged, the test.p7m contains the 
// contents of the input file and the signature.
string inFile = "test.txt";
string outFile = "testp7m";
success = crypt.CreateP7M(inFile,outFile);
if (success != true) {
    Debug.WriteLine(crypt.LastErrorText);
    return;
}

Debug.WriteLine("Success!");