使用c#将sql查询中的值赋给CRM中的字段

我试图为CRM创建一个插件，查询mysql数据库并从数据库中提取数据，并将其添加到CRM中的一个字段。到目前为止，我所拥有的是下面这一点，但我不确定如何在crm中分配一个表列的字段值?

`namespace Microsoft.Crm.Sdk.Samples
 {
   public class AssignSMSPlugin: IPlugin
   {
    /// <summary>
    /// A plug-in that creates a follow-up task activity when a new account is created.
    /// </summary>
    /// <remarks>Register this plug-in on the Create message, account entity,
    /// and asynchronous mode.
    /// </remarks>
    public void Execute(IServiceProvider serviceProvider)
    {
        //Conect to mySQl Database
        String str ="";
        MySqlConnection con = null;
        MySqlDataReader reader = null;
        try 
        {
            con = new MySqlConnection(str);
            con.Open();
            //Select statement to query table to get certain columns
            string cmdText = "SELECT col1, col2, col3 FROM table1";
            MySqlCommand cmd = new MySqlCommand(cmdText, con);
            reader = cmd.ExecuteReader();
           // while (reader.Read())
          //  {
          //      Console.WriteLine(reader.GetString(0));
         //   }
        //Extract the tracing service for use in debugging sandboxed plug-ins.
        ITracingService tracingService =
            (ITracingService)serviceProvider.GetService(typeof(ITracingService));
        // Obtain the execution context from the service provider.
        IPluginExecutionContext context = (IPluginExecutionContext)
            serviceProvider.GetService(typeof(IPluginExecutionContext));
        // The InputParameters collection contains all the data passed in the message request.
        if (context.InputParameters.Contains("Target") &&
            context.InputParameters["Target"] is Entity)
        {
            // Obtain the target entity from the input parameters.
            Entity entity = (Entity)context.InputParameters["Target"];
            // Verify that the target entity represents an account.
            // If not, this plug-in was not registered correctly.
            if (entity.LogicalName != "customer")
                return;
            try
            {
                // Create a sms activity.Assign table column to  field in crm 
                Entity assign = new Entity("SMS Message");
                assign["to"] = "";
                assign["subject"] = "";
                assign["contact"] = ;
                assign["regardingobjectid"] = ;

                // Refer to the account in the task activity.
                if (context.OutputParameters.Contains("id"))
                {
                    Guid regardingobjectid = new Guid(context.OutputParameters["id"].ToString());
                    string regardingobjectidType = "customer";
                    assign["regardingobjectid"] =
                    new EntityReference(regardingobjectidType, regardingobjectid);
                }
                // Obtain the organization service reference.
                IOrganizationServiceFactory serviceFactory = (IOrganizationServiceFactory)serviceProvider.GetService(typeof(IOrganizationServiceFactory));
                IOrganizationService service = serviceFactory.CreateOrganizationService(context.UserId);
                // Create the task in Microsoft Dynamics CRM.
                tracingService.Trace("AssignSMSPlugin: Creating the SMS Activity.");
                service.Create(assign);
            }
            catch (FaultException<OrganizationServiceFault> ex)
            {
                throw new InvalidPluginExecutionException("An error occurred in the AssignSMSPlugin plug-in.", ex);
            }
            catch (Exception ex)
            {
                tracingService.Trace("AssignSMSPlugin: {0}", ex.ToString());
                throw;
            }
        }
    }
}`