public string ReadFromBlockchain(byte[] text) { byte[] privKey = "1dd37fba80fec4e6a6f13fd708d8dcb3b29def768017052f6c930fa1c5d90bbb".HexToBytes(); // can be any valid private key var myKeys = new KeyPair(privKey); var response = _api .CallContract(myKeys, _contractScriptHash.HexToBytes(), "readFromBlockchain", new object[] { text }); response = _api.InvokeScript(_contractScriptHash.HexToBytes(), "readFromBlockchain", new object[] { text }); return(response.transaction.Hash.ToString()); }