相关疑难解决方法(0)

在以下情况下,我经常遇到一个错误,例如"无法从'方法组'转换为'字符串'"

var list = new List<string>();
// ... snip
list.Add(someObject.ToString);

当然最后一行有一个拼写错误,因为我忘记了之后的调用括号ToString.正确的形式是:

var list = new List<string>();
// ... snip
list.Add(someObject.ToString()); // <- notice the parentheses

但是我想知道什么是方法组.谷歌也不是MSDN的帮助.

我正在将一些东西从一个mysql服务器迁移到一个sql server但我无法弄清楚如何使这个代码工作:

using (var context = new Context())
{
    ...

    foreach (var item in collection)
    {
        IQueryable<entity> pages = from p in context.pages
                                   where  p.Serial == item.Key.ToString()
                                   select p;
        foreach (var page in pages)
        {
            DataManager.AddPageToDocument(page, item.Value);
        }
    }

    Console.WriteLine("Done!");
    Console.Read();
}

当它进入第二个时foreach (var page in pages)它抛出一个异常说:

LINQ to Entities无法识别方法'System.String ToString()'方法,并且此方法无法转换为存储表达式.

谁知道为什么会这样？

如何将int和int转换为字符串？以下都不起作用:

from s in ctx.Services
    where s.Code.ToString().StartsWith("1")
    select s

from s in ctx.Services
    where Convert.ToString(s.Code).StartsWith("1")
    select s

from s in ctx.Services
    where ((string)s.Code).ToString().StartsWith("1")
    select s

编辑

我得到的错误是:

LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method cannot be translated into a store expression

在MVC3 Web应用程序中获取错误. LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method cannot be translated into a store expression.

当我尝试从查询中使用EF获取值时:

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();
        }
    }