(C#) Extract a File from a .p7m (PKCS7 Signed-Data)

C# example to extract the original file from a .p7m (Signed-Data PKCS7 Format) The .p7m contains the signed contents of the original file. It can be verified and restored by calling VerifyP7M.

Download: Chilkat .NET Assemblies

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) {
    textBox1.Text += crypt.LastErrorText + "\r\n";
    return;
}

string outFile;
outFile = "/Users/chilkat/testData/pdf/sample.pdf";
string inFile;
inFile = "/Users/chilkat/testData/p7m/sample.pdf.p7m";

//  Verify and restore the original file:
success = crypt.VerifyP7M(inFile,outFile);
if (success == false) {
    textBox1.Text += crypt.LastErrorText + "\r\n";
    return;
}

MessageBox.Show("Success!");