非静态方法需要一个目标.实体框架 5 代码优先 [英] Non-static method requires a target. Entity Framework 5 Code First

问题描述

我收到错误非静态方法需要目标."当我运行以下查询时:

I am getting the error "Non-static method requires a target." when I run the following query:

var allPartners = DbContext.User
                           .Include(u => u.Businesses)
                           .Where(u => u.Businesses.Any(x => x.Id == currentBusinessId))
                           .ToList();

我的实体定义如下:

public class User : Entity
{
    public virtual List<Business> Businesses { get; set; }
}

public class Business : Entity
{
    public virtual List<User> Users { get; set; }
}

public class Entity
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public Guid Id { get; set; }
}

我的上下文是这样配置的；

And my context is configured like this;

public class Context : DbContext, IDatabaseSession
{
    public DbSet<Business> Business { get; set; }
    public DbSet<User> User { get; set; }

    public Context()
        : base("DefaultConnection")
    {

    }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        modelBuilder.Conventions.Remove
            <System.Data.Entity.ModelConfiguration.Conventions.PluralizingTableNameConvention>();

        Database.SetInitializer(new MigrateDatabaseToLatestVersion<Context, Configuration>());

        modelBuilder.Entity<User>()
            .HasMany(u => u.Businesses)
            .WithMany(b => b.Users);
    }
}

我做错了什么?

推荐答案

问题归结为查询.我原来的问题有这个查询:

The problem boiled down to the query. My original question had this query:

var allPartners = DbContext.User
                       .Include(u => u.Businesses)
                       .Where(u => u.Businesses.Any(x => x.Id == currentBusinessId))
                       .ToList();

这不太准确，实际上我已经删除了错误，试图简洁地提出我的问题.查询实际上是:

Which wasn't quite accurate, I had in fact removed the error in an attempt to ask my question succinctly. The query was actually:

var currentBusiness = GetBusiness();
var allPartners = DbContext.User
                       .Include(u => u.Businesses)
                       .Where(u => u.Businesses.Any(x => x.Id == currentBusiness.Id))
                       .ToList();

当 GetBusiness 方法返回 null 时，错误被抛出.只需确保我没有将 null 对象传递到表达式中，错误就会停止.

When the GetBusiness method returned null the error was thrown. Simply ensuring that I don't pass a null object into the expression made the error stop.

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