Sign a File to Create a .p7m File

C# example to sign a file creating a .p7m file as output. The .p7m contains the signed contents of the original file. It can be verified and restored by calling VerifyP7M.

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

//  Any string argument automatically begins the 30-day trial.
bool success;
success = crypt.UnlockComponent("30-day trial");
if (success != true) {
    MessageBox.Show("Crypt component unlock failed");
    return;
}

//  Find our digital certificate from the Current User certificate store.
Chilkat.CreateCS ccs = new Chilkat.CreateCS();
Chilkat.CertStore certStore;
certStore = ccs.OpenCurrentUserStore();
Chilkat.Cert cert;
cert = certStore.FindCertBySubjectCN("Chilkat Software, Inc.");
if (cert == null ) {
    MessageBox.Show(cert.LastErrorText);

    return;
}

//  Tell the crypt component to use this cert.
crypt.SetSigningCert(cert);

//  We can sign any type of file, creating a .p7s as output:
success = crypt.CreateP7M("test.xml","test.p7m");
if (success == false) {
    MessageBox.Show(crypt.LastErrorText);

    return;
}

//  Verify and restore the original file:
crypt.SetVerifyCert(cert);

success = crypt.VerifyP7M("test.p7m","testRestored.xml");
if (success == false) {
    MessageBox.Show(crypt.LastErrorText);

    return;
}

MessageBox.Show("Success!");