public List<EnergyFlowGraph> GetData()

        {

            var data = db.EnergyFlowGraph.Select(d => new

            {

                ClassID = d.ClassID,

                ParentClassID = d.ParentClassID,

                ClassName = d.ClassName,

            }).ToList();

             return data;

            //报错： 无法将类型“System.Collections.Generic.List<anonymous type:string ClassID,string ClsssName>”隐式转换为“System.Collections.Generic.List<Ecology.Model.EnergyFlowGraph>”

            // 根据提示可知错误的原因 匿名类型anonymous type

            //d => new EnergyFlowGraph

            //解决方案一： new EnergyFlowGraph

            //var data = db.EnergyFlowGraph.Select(d => new EnergyFlowGraph

            //{

            //    ClassID = d.ClassID,

            //    ParentClassID = d.ParentClassID,

            //    ClassName = d.ClassName,

            //}).ToList();

            //return data;

            //解决方案二：foreach遍历

            //var list = new List<EnergyFlowGraph>();

            //foreach (var temp in data)

            //{

            //    var energyFlowGraph = new EnergyFlowGraph();

            //    energyFlowGraph.ClassID = temp.ClassID;

            //    energyFlowGraph.ClassName = temp.ClassName;

            //    energyFlowGraph.ParentClassID = temp.ParentClassID;

            //    list.Add(energyFlowGraph);

            //}

            //return list;

        }

namespace Ecology.Models

{

    using System;

    using System.Collections.Generic;

    public partial class EnergyFlowGraph

    {

        public string ClassID { get; set; }

        public string ParentClassID { get; set; }

        public string ClassName { get; set; }

    }

}