c# - The following throws 'is a Method but treated like a type'

Question

The most confusing error I have ever seen in ASP. I have done method calls like this before, and have no issue in other spots of my code.

First of all the class:

namespace LocApp.Helpers.Classes.LocationHelper
{
    public class QueryHelper
    {
        private LocAppContext db = new LocAppContext();

        public static IEnumerable<Service> getAllService()
        {
            using (var db = new LocAppContext())
            {
                var service = db.Locations.Include(s => s.LocationAssignment);

                var serv = (from s in db.Services
                            where s.active == true
                            select s).ToList();
                return serv;
            }
        }
    }
}

Pretty easy to understand whats going on. So lets call the method:

IEnumerable<LocApp.Models.Service> Service = new LocApp.Helpers.Classes.LocationHelper.QueryHelper.getAllService(Model.id);

getAllServices(Model.id) is throwing the error "is a method but treated like a type" , um no its not be treated like a type....

whats going on?

Answer 1

好吧，就像错误消息所说的那样。getAllService()是一种方法：

public static IEnumerable<Service> getAllService()

但是你试图使用它，就好像它是一个带有构造函数的类型：

Service = new LocApp.Helpers.Classes.LocationHelper.QueryHelper.getAllService(...)

这new部分是这里的错误。你不想调用构造函数，你只想调用一个方法。这是一个静态方法，所以你不需要实例 - 你可以使用：

Service = LocApp.Helpers.Classes.LocationHelper.QueryHelper.getAllService(...)

请注意，如果您有适当的using指令，遵循 .NET 命名约定并注意单数/复数名称，您的代码将更容易遵循：

var services = QueryHelper.GetAllServices(...);

Answer 2

你不是简单的意思吗：

IEnumerable<LocApp.Models.Service> Service = LocApp.Helpers.Classes.LocationHelper.QueryHelper.getAllService();

从本质上讲，摆脱该new位，并且该方法也不使用任何参数-我假设您在删除该new位后会遇到该问题。

Answer 3

您的 getAllService 方法不带任何参数，因此您应该在没有参数的情况下调用它。它也是一个静态方法，所以不要使用new关键字：

IEnumerable<LocApp.Models.Service> Service = LocApp.Helpers.Classes.LocationHelper.QueryHelper.getAllService();