public class SqlWebDataService : IDataService
{
    public bool IsValid()
    {
        WebDataService oService = new WebDataService();
        bool retVal = oService.IsValid();
        oService.Dispose();
        return retVal;
    }

    public DataSet ExecuteQuery(IDbCommand Command, 
        string ResultName)
    {
        WebDataService oService = new WebDataService ();
        DataSet dsResult = oService.ExecuteQuery(
            this.GetSerializedCommand(Command),ResultName);
        oService.Dispose();
        return dsResult;
    }

    public void ExecuteNonQuery(IDbCommand Command)
    {
        WebDataService oService = new WebDataService ();
        oService.ExecuteNonQuery(
            this.GetSerializedCommand(Command));         
        oService.Dispose();
    }

    public object ExecuteScalar(IDbCommand Command)
    {
        WebDataService oService = new WebDataService ();
        object result = oService.ExecuteScalar(
            this.GetSerializedCommand(Command));         
        oService.Dispose();
        return result;
    }

    public IDbCommand GetCommandObject()
    {
        return new SqlCommand();
    }

    public void AddCommandParameter(IDbCommand command, 
        string parameterName, object parameterValue)
    {
        SqlCommand myCommand = (SqlCommand)command;
        myCommand.Parameters.Add(parameterName,parameterValue);
    }

    private string GetSerializedCommand(IDbCommand command)
    {
        SqlCommand cmd = (SqlCommand)command;
        StringBuilder sb = new StringBuilder();
        sb.Append(
            "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\r\n");
        sb.Append("<command>\r\n");
        sb.Append("  <text>"+command.CommandText+"</text>\r\n");
        sb.Append("  <type>"+
            command.CommandType.ToString()+"</type>\r\n");
        sb.Append("  <parameters>\r\n");

        foreach(SqlParameter para in cmd.Parameters)
        {
            sb.Append("    <parameter name=\""+
                para.ParameterName+"\">");
            sb.Append(para.Value.ToString());
            sb.Append("</parameter>\r\n");
        }

        sb.Append("  </parameters>\r\n");
        sb.Append("</command>\r\n");
        return sb.ToString();
    }
}