The CertGetNameString function obtains the subject or issuer name from a certificate CERT_CONTEXT structure and converts it to a null-terminated character string.

[DllImport("crypt32.dll", EntryPoint = "CertGetNameString", CharSet = CharSet.Auto, SetLastError = true)]

static extern UInt32 CertGetNameString(IntPtr CertContext, UInt32 lType, UInt32 lFlags, IntPtr pTypeParameter, System.Text.StringBuilder str, UInt32 cch);

Declare Function CertGetNameString Lib "Crypt32.dll" Alias "CertGetNameStringW" ( _

Ensure you use StrPtr and that the function signature is "CertGetNameStringW", or you will regularly crash your program!

System.UInt32 nChars = CertGetNameString(certContext,

szNameString = CertGetNameString(hCert_Context&, _

Documentation

[CertGetNameString] on MSDN

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