how can i use encode and decode with sm2

[Taoja]

i see the test code for encode and decode like this

#[test]
    fn test_sig_encode_and_decode() {
        let string = String::from("abcdabcdabcdabcdabcdabcdabcdabcdabcdabcdabcd");
        let msg = string.as_bytes();

        let ctx = SigCtx::new();
        let (pk, sk) = ctx.new_keypair();

        let signature = ctx.sign(msg, &sk, &pk);
        let der = signature.der_encode();
        let sig = Signature::der_decode(&der[..]).unwrap();
        assert!(ctx.verify(msg, &pk, &sig));

        let signature = ctx.sign(msg, &sk, &pk);
        let der = signature.der_encode();
        let sig = Signature::der_decode_raw(&der[2..]).unwrap();
        assert!(ctx.verify(msg, &pk, &sig));
    }

but i need a methods to encrypt plaintext.

[HaoXuan40404]

You can use Hex or base64 to change bytes to string