Linq 等价物

Question

foreach (ParameterGroup paramGroup in ParamGroups)
        {
            foreach (Parameter parameter in paramGroup.ParameterList)
            {
                if (parameter.ParameterId == parameterId)
                    return paramGroup.GroupId;
            }
        }

什么是 LINQ 等价的？

Answer 1

return (from paramGroup in ParamGroups
        from parameter in paramGroup.ParameterList
        where parameter.ParameterId == parameterId
        select paramGroup.GroupId).FirstOrDefault();