使用 asp.NET Core Identity 设置 DropdownList 值

Question

我正在尝试清理一些乱七八糟的东西。我有一个正确填充的 Company 下拉列表。但我不知道如何让下拉菜单工作的选定值。我看过很多例子，但是在我们使用它的上下文中，这让我感到困惑。 我们正在使用 asp.Net Core Identity。

感谢任何指导！

下拉列表：

   <div class="form-group row text-center">
     <label asp-for="CompanyLists" class="col-sm-3 text-right col-form-label labelFont"></label>
       <div class="col-sm-8">
         @Html.DropDownListFor(model => model.SelectedCompany, new SelectList(Model.CompanyLists.OrderBy(x => x.CompanyName), "CompanyID", "CompanyName"), "-- Select Company --", new { @class = "form-control" })
           <span asp-validation-for="CompanyLists" class="text-danger"></span>
       </div>
   </div>

方法：

        // EDIT USER : GET-----------------------------------------------------
        [HttpGet]
        public async Task<IActionResult> EditUser(string id)
        {
            //GET USER INFORMATION - EXIT IF USER DOESN'T EXIST
            var user = await userManager.FindByIdAsync(id);
            if (user == null)
            {
                ViewBag.ErrorMessage = $"User with Id = {id} cannot be found";
                return View("NotFound");
            }

     //USER INFORMATION ---------------------------------------
            var model = new EditUserViewModel
            {
                Id = user.Id,
                Email = user.Email,
                UserName = user.UserName,
                FirstName = user.FirstName,
                LastName = user.LastName,
                Title = user.Title,
                Address = user.Address,
                City = user.City,
                State = user.State,
                //SelectedCompany = user.Company.ToString()
            };

    //COMPANY DROPDOWN INFO------------------------------------
            var company = from c in companyRepository.GetCompanys() select c;
            foreach (var c in company)
            {
                ////Store this information into the company list in the viewmodel
                var companyinfo = new EditUserViewModel.CompanyList
                {
                    CompanyName = c.CompanyName,
                    CompanyID = c.CompanyId,
                };

                model.CompanyLists.Add(companyinfo);
            };

     //GET LIST OF ROLES(RoleID, RoleName)
            var roles = roleManager.Roles;

            foreach (var RoleName in roles)
            {
                //Execute identity method to get full information for the Role and store into an object (roleinfo)
                var roleString = RoleName.Name;
                var fullRoleInfo = await roleManager.FindByNameAsync(roleString);
                //Store this information into the Role list in the viewmodel
                var roleinfo = new EditUserViewModel.Role
                {
                    RoleName = fullRoleInfo.Name,
                    RoleID = fullRoleInfo.Id,
                };

                if (await userManager.IsInRoleAsync(user, roleString))
                {
                    roleinfo.IsSelected = true;
                }
                else
                {
                    roleinfo.IsSelected = false;
                }

                model.Roles.Add(roleinfo);
            };

     //*****************************************************
            //IDENTITY CLAIM INFORMATION ------------------------------

            var existingUserClaims = await userManager.GetClaimsAsync(user);

            foreach (Claim claim in ClaimStore.AllClaims)
            {
                var userClaims = new EditUserViewModel.Claim
                {
                    ClaimType = claim.Type
                };


                if (existingUserClaims.Any(c => c.Type == claim.Type && c.Value == "true"))
                {
                    userClaims.IsSelected = true;
                }
                else
                {
                    userClaims.IsSelected = false;
                }

                model.Claims.Add(userClaims);
            }

       return PartialView("~/Views/Modals/_EditUserModalPartial.cshtml", model);
      }

这就是我开始感到困惑的地方。我们有一个 EditUserViewModel.cs；但是，我们也有 ApplicationUser.cs 模型，我无法弄清楚所选公司如何进入 ApplicationUser.cs 或我需要做些什么来完成这项工作。

EditUserViewModel：

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Security.Claims;
using System.Threading.Tasks;

namespace PortalDev.Models.ViewModels
{
    public class EditUserViewModel
    {

        public EditUserViewModel()
        {
            Claims = new List<Claim>();
            Roles = new List<Role>();
            //CompanyLists = new List<ICompanyRepository>();
            CompanyLists = new List<CompanyList>();
        }

        //ROLES ---------------------------------------------
        public class Role
        {
            public string RoleName { get; set; }
            public string RoleID { get; set; }
            public bool IsSelected { get; set; }

        }
        public List<Role> Roles { get; set; }

        //CLAIMS----------------------------------------------
        public class Claim
        {
            public string ClaimType { get; set; }
            public string ClaimID { get; set; }
            public bool IsSelected { get; set; }
        }
        public List<Claim> Claims { get; set; }

        //COMPANY DROPDOWN--------------------------------------
        public class CompanyList
        {
            public string CompanyName { get; set; }
            public int CompanyID { get; set; }
        }
        [Display(Name = "Company")]
        public List<CompanyList> CompanyLists { get; set; }   //List of Companies for dropdown
        public string SelectedCompany { get; set; }


        //USER INFORMATION --------------------------------------
        public string Id { get; set; }
        //[Required]
        public string UserName { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Title { get; set; }
        [Required]
        [EmailAddress]
        public string Email { get; set; }
        public string Address { get; set; }
        public string City { get; set; }
        public string State { get; set; }
        public int CompanyId { get; set; }
    }
}

ApplicationUser.cs

using Microsoft.AspNetCore.Identity;
using PortalDev.Models.ViewModels;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
//Extends built in IdentityUser class
namespace PortalDev.Models
{
    public class ApplicationUser : IdentityUser
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Title { get; set; }

        public string Address{ get; set;}
        public string City { get; set; }
        public string State { get; set; }

        public Company Company { get; set; }
    }
}

UserMaint.html

@model IEnumerable<PortalDev.Models.ApplicationUser>

<link rel="stylesheet" href="~/css/Maintenance.css" />
<link rel="stylesheet" href="~/css/Index.css" />


<div class="tableContainer">

    <div class="maintHeader">
        <div class="headerText">
            All Users

            <button class="sqButton btnBlue float-right" title="Register" data-toggle="ajax-modal" data-target="#register" data-url="@Url.Action("Register", "Home")"><i class="glyphicon glyphicon-plus"></i></button>
        </div>
    </div>

    @if (Model.Any())
    {
        //--Table Header Declaration--
        <div class="wrapper">
            <div class="scrollTable">

                <table class="table table-hover table-md ">

                    <thead>
                        <tr>
                            <th class="text-left tableHead d-none">Id</th>
                            <th class="text-left tableHead">Company</th>
                            <th class="text-left tableHead">User Name</th>
                            <th class="text-left tableHead">First Name</th>
                            <th class="text-left tableHead">Last Name</th>
                            <th class="text-left tableHead">Title</th>
                            <th class="text-left tableHead">City</th>
                            <th class="text-left tableHead">State</th>
                            <th class="text-left tableHead text-right">Remove</th>
                        </tr>
                    </thead>

                    @*--Table Body For Each to pull DB records--*@
                    <tbody>
                        @foreach (var user in Model)
                        {
                            @Html.Partial("~/Views/Administration/Users/UserTable.cshtml", user)
                        }
                    </tbody>

                </table>
            </div>
        </div>

    }
    <div id="modal-placeholder"></div>
</div>

Answer 1

如果您想在EditUser.cshtml上显示用户在编辑之前拥有的Company，您可以对ApplicationUser模型、EditUser方法和下拉列表进行如下修改：

ApplicationUser.cs

public class ApplicationUser : IdentityUser
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Title { get; set; }

    public string Address { get; set; }
    public string City { get; set; }
    public string State { get; set; }

    public int CompanyId { get; set; }
    [ForeignKey("CompanyId")]
    public Company Company { get; set; }
}

EditUser 方法

var model = new EditUserViewModel
 {
            Id = user.Id,
            Email = user.Email,
            UserName = user.UserName,
            FirstName = user.FirstName,
            LastName = user.LastName,
            Title = user.Title,
            Address = user.Address,
            City = user.City,
            State = user.State,
            CompanyId = user.CompanyId
 };

公司下拉列表

<div class="col-sm-8">
  @Html.DropDownListFor(model => model.CompanyId, new SelectList(Model.CompanyLists.OrderBy(x => x.CompanyName), "CompanyID", "CompanyName"), "-- Select Company --", new { @class = "form-control" })
  <span asp-validation-for="CompanyId" class="text-danger"></span>
</div>