using System;

using System.Security.Cryptography;

using System.Text;

​

public class Program

{

    public static void Main()

    {

        string user="abc";

        string pass="abc123";

        string data = "{\"username\":\"" + user + "\",\"password\":\"" + pass + "\"}";

        string publicKey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCDY1DzbqoavP8UVPYARHpy+zPlaFiBdf3imr5m4RdbHCwMueevk+NoWV2dqL/LBnk8oWMqWkgMDnTleXe/jvj6zQEuuCoBVDiZq4k0JXbHdTmXg0/fH7d9YD0BsSkpSJH8A9RBSnjvIzKLNHXKTUyxG1QIIKbU2lhVAB/jK2UtdwIDAQAB";

        string _encrypt = Encrypt(data, publicKey);

        Console.WriteLine(_encrypt);

    }

     public static string Encrypt(string data, string publicKey)

        {

            RSA rsa = RSA.Create();

​

            rsa.ImportSubjectPublicKeyInfo(Convert.FromBase64String(publicKey), out int noNeed);

​

            byte[] encrypted = rsa.Encrypt(Encoding.UTF8.GetBytes(data), RSAEncryptionPadding.Pkcs1);

​

​

            return Convert.ToBase64String(encrypted);

        }

}