asp.net-mvc – 为什么LINQ to Entities不能识别方法’System.String ToString()？

在MVC3 Web应用程序中获取错误。
LINQ to Entities不识别方法“System.String ToString()”方法，并且此方法不能转换为存储表达式。

当我尝试从查询获取值使用EF：

public class DataRepository
    {
        public mydataEntities1 dbContext = new mydataEntities1();

        public List<SELEctListItem> GetPricingSecurityID()
        {
        var pricingSecurityID = (from m in dbContext.ReporTing_DailyNAV_Pricing
                                     SELEct new SELEctListItem
                                         {
                                                Text = m.PricingSecurityID.ToString(),Value = m.PricingSecurityID.ToString()
                                         });

        return pricingSecurityID.ToList();
        }
    }

var pricingSecurityID = (from m in dbContext.ReporTing_DailyNAV_Pricing
                                     SELEct m.PricingSecurityID).AsEnumerable()
    .SELEct(x => new SELEctListItem{ Text = x.ToString(),Value = x.ToString() });