INSERT 语句与 FOREIGN KEY 约束“FK_Projets_Plannings_ID_Projet”冲突

Question

我在调试时遇到此异常错误

Microsoft.EntityFrameworkCore.DbUpdateException: 'An error occurred while saving the entity changes. See the inner exception for details. Inner Exception : SqlException: The INSERT statement conflicted with the FOREIGN KEY constraint "FK_Projets_Plannings_ID_Projet". The conflict occurred in database "winky", table "dbo.Plannings", column 'ID_Planning'.'

。我查看了现有的解决方案。我不明白如何解决我的案例中的错误。没找到类似的东西。我试过。所以请我感谢任何帮助。这是我的代码和有问题的模型。 PS：我不使用 SSQM。

程序.cs

using Projet.Models;
using Microsoft.EntityFrameworkCore;
using System;
using Projet;

using (ProjetContext context = new ProjetContext())
{
    Projets projet = new Projets()
    {
        ID_Projet = 1,
        Nom_Projet = "Cut_Line generator",
        Description_Projet = "",
        Version_Projet = "41",
        Révision_Projet = "0",
        Statut_Projet = "Validé"
    };
    DateTime dateDebut = new DateTime(2018, 11, 30);

    Plannings planning = new Plannings()
    {
        //ID_Planning = 1,
        Date_Début = dateDebut,
        ID_Projet = 1
    };
    
    
    
    context.SaveChanges();
}

Plannings.cs 模型

using System.ComponentModel.DataAnnotations;
namespace Projet.Models
{
    public class Plannings
    {
        [Key] 
        public int ID_Planning { get; set; }
        [Required]
        public System.DateTime Date_Début { get; set; }
        
        public Nullable<System.DateTime> Date_Fin { get; set; }
        public System.DateTime Date_Est { get; set; }
        public int ID_Projet { get; set; }
        public Projets Projets { get; set; } = null!;

    }
}

ProjetContext.cs

//using System.Data.Entity;
using Microsoft.EntityFrameworkCore;
using Projet.Models;

namespace Projet
{
    public class ProjetContext : DbContext
    {

        public ProjetContext() 
        {

        }

        public ProjetContext(DbContextOptions options) : base(options)
        {
        }
        public DbSet<Plannings> Plannings { get; set; }
        public DbSet<Projets> Projets { get; set; }
        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder.UseSqlServer("Server=;Database=;User Id=;Password=;TrustServerCertificate=True;");
        }
protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
               
             modelBuilder.Entity<Projets>()
                .HasOne(e => e.Plannings)
                .WithOne(e => e.Projets)
                .HasForeignKey<Projets>(e => e.ID_Projet).IsRequired();

            }

    }


}

///

Projets.cs

    using System.ComponentModel.DataAnnotations;
    
    namespace Projet.Models
    {
        public class Projets
        {
            [Key]
            public int ID_Projet { get; set; }
    
            [Required]
            public string Nom_Projet { get; set; }
    
            public string Description_Projet { get; set; }
    
            [Required]
            public string Version_Projet { get; set; }
    
            [Required]
            public string Révision_Projet { get; set; }
    
            [Required]
            public string Statut_Projet { get; set; }
          public Plannings? Plannings { get; set; }
 }
    }

        


   

Answer 1

您似乎忘记将

projet

实体上的 Plannings 属性分配给

planning

实体，以便上下文可以正确跟踪两个相关对象。