Web API POST 请求添加新记录，但所有属性都设置为 NULL？

Question

我有一个 Web API POST 请求，该请求应该使用在正文中找到的属性作为 JSON 将新记录添加到特定表中。但是，当输入所有属性（我认为是正确的）时，请求最终将添加一条新记录，但是无论出于何种原因，所有属性都将设置为 NULL？

以下是我的 API Post 请求：

/*Define URL endpoint for adding a single role*/
        [System.Web.Http.Route("api/Roles/addRole")]
        /*HttpPost header, ensures only the usage of POST requests*/
        [System.Web.Mvc.HttpPost]
        /*Main return new list with added role*/
        public List<dynamic> addRole([FromBody] Roles roles)
        {
            if (roles != null)
            {
                /*Create an instance of the UltimateDB*/
                UltimateDBEntities db = new UltimateDBEntities();
                /*Optimize memory usage by disabling proxy creation*/
                db.Configuration.ProxyCreationEnabled = false;
                db.Roles.Add(roles);
                db.SaveChanges();
                return getAllRoles();
            }
            else
            {
                return null;
            }
            
        }

上面应该使用用户输入的正文 (JSON) 中的数据向“角色”表添加一条记录。我已经使用 Postman 对此进行了测试，返回的只是一条新记录，其所有属性都设置为 NULL。

例如我会输入这个：

{
    "Name": "Lab Employee",
    "Description": "User only has read rights",
    "Tenant_rental": 1,
    "Property_Module": 0,
    "Employee_Management": 0,
    "Reports": 1,
    "administration": 1,
    "user_Password_access": 0,
    "Building_Management": 0,
    "Credit_Bureau": 1
}

并将其作为我的新记录：

{
        "ID": 23,
        "Name": null,
        "Description": null,
        "Tenant_rental": null,
        "Property_Module": null,
        "Employee_Management": null,
        "Reports": null,
        "administration": null,
        "user_Password_access": null,
        "Building_Management": null,
        "Credit_Bureau": null
    }

我的角色课程：

namespace U18043039_HW1.Models
{
    using System;
    using System.Collections.Generic;
    
    public partial class Roles
    {
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
        public Roles()
        {
            this.User_Table = new HashSet<User_Table>();
        }
    
        public int Role_ID { get; set; }
        public string Role_Name { get; set; }
        public string Role_Description { get; set; }
        public Nullable<bool> Role_Tenant_rental { get; set; }
        public Nullable<bool> Role_Property_Module { get; set; }
        public Nullable<bool> Role_Employee_Management { get; set; }
        public Nullable<bool> Role_Reports { get; set; }
        public Nullable<bool> Role_administration { get; set; }
        public Nullable<bool> Role_user_Password_access { get; set; }
        public Nullable<bool> Role_Building_Management { get; set; }
        public Nullable<bool> Role_Credit_Bureau { get; set; }
    
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
        public virtual ICollection<User_Table> User_Table { get; set; }
    }
}

Answer 1

使用此数据进行测试：

{
    "Role_Name": "Lab Employee",
    "Role_Description": "User only has read rights",
    "Role_Tenant_rental": True,
    "Role_Property_Module":False,
    ... and so on
}