this ViewDataDictionary instance requires a model item of type 'System.Collections.Generic.IEnumerable Error[Answered] RSS

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  ShahadAlshuh...

  Member

  15 Points

  33 Posts

  this ViewDataDictionary instance requires a model item of type 'System.Collections.Generic.IEnume...

  Jul 17, 2020 01:54 PM|ShahadAlshuhail|LINK

  I got this error multiple times, and i tried to understand what is exactly wrong but unfortunately i couldn't. So , Any help in this is much appreciated.

  Error:

  InvalidOperationException: The model item passed into the ViewDataDictionary is of type 'TestApplication.Models.Approval', but this ViewDataDictionary instance requires a model item of type 'System.Collections.Generic.IEnumerable`1[TestApplication.Models.ViewModels.RequestApprovalViewModel]'.

  I have 2 models (Requests) & (Approvals). one request could have many approvals.

  Here is My Models.

  public class Request
      {
          public int Id { get; set; }
          public string Type { get; set; }
          public DateTime Date { get; set; }
          public int Seats { get; set; }
          public bool isDone { get; set; }
          public string InstitutionId { get; set; }
  
          [ForeignKey("InstitutionId")]
          public virtual Institution Institution { get; set; }
  
          //public virtual ICollection<Approval> Approvals { get; set; }
      }
  
    public class Approval
      {
          public int Id { get; set; }
          public string Status { get; set; }
          public DateTime Date { get; set; }
          public int RequestId { get; set; }
          public string ManagerId { get; set; }
  
          [ForeignKey("RequestId")]
          public virtual Request Request { get; set; }
  
          [ForeignKey("ManagerId")]
          public virtual ApplicationUser Manager { get; set; }
      }

  Here i have the View where i'm displaying all requests where (isDone == true). Next to each request i have button to display a table in a modal popup of this request history.

  @model IEnumerable<Approval>
  
  @{
      ViewData["Title"] = "Requests";
  }
  <div class="border">
      <div>
          @if (Model.Count() > 0)
          {
              <table class="table table-striped">
                  <tr class="table-secondary">
                      <th>
                        Institution Name 
                      </th>
                      <th>
                           Approval Status
                      </th>
                      <th>
                          Request History 
                      </th>
                   
                  </tr>
                  @foreach (var item in Model)
                  {
                      <tr>
                          <td>
                              @Html.DisplayFor(m => item.Request.Institution.Name)
                          </td>
                          <td>
                              @Html.DisplayFor(m => item.Status)
                          </td>
                          <td>
                              <button type="submit" class="btn btn-success anchorDetail" data-target="#modal-@item.Request.Institution.AdminId" data-toggle="modal">
                                  Show Details
                              </button>
                          </td>
                          <td>
                              <div class="modal fade" id="modal-@item.Request.Institution.AdminId" tabindex="-1" role="dialog" aria-hidden="true">
                                  <div class="modal-dialog-centered modal-dialog" role="document">
                                      <div class="modal-content">
                                          <div class="modal-header bg-success text-light justify-content-center">
                                              <h5 class="modal-title">Request Details</h5>
                                          </div>
                                          <div class="modal-body justify-content-center" id="MyModalContent">
                                              @await Html.PartialAsync("_RequestHistory", item)
                                          </div>
                                          <div class="modal-footer">
                                              <button type="button" class="btn btn-secondary" data-dismiss="modal">إغلاق</button>
                                          </div>
                                      </div>
                                  </div>
                              </div>
                          </td>
                      </tr>
                  }
              </table>
          }
          else
          {
              <p>No Requests Exists...</p>
          }
      </div>
  </div>
  
  @section scripts
  {
      <script>var PostBackURL = '/Request/History';
          $(function () {
              $(".anchorDetail").click(function () {
                  var $buttonClicked = $(this);
                  var id = $buttonClicked.attr('data-id');
                  $.ajax({
                      type: "GET",
                      url: PostBackURL,
                      contentType: "application/json; charset=utf-8",
                      data: { "Id": id },
                      cache: false,
                      datatype: "json",
                      success: function (data) {
                          $('#MyModalContent').html(data);
                          $('#myModal').modal('show');
                      },
                      error: function () {
                          alert("Dynamic content load failed.");
                      }
                  });
              })</script>
  }
  <div class="modal fade" id="MyModal" tabindex="-1" role="dialog"
       aria-labelledby="myModalLabel">
      <div id='MyModalContent'></div>
  </div>

  Here is my Controller

  [Authorize(Roles = SD.ManagerUser)]
  public async Task<IActionResult> Requests()
  {
      var requests = await _db.Approval
          .Include(c => c.Request)
           .ThenInclude(c => c.Institution)
          .Where(c => c.Request.isDone == true) //should be true 
         
          //.ThenInclude(c => c.Admin)
          .ToListAsync();
      return View(requests);
  }
  
  
  public async Task<IActionResult> History()
  {
      RequestApprovalViewModel model = new RequestApprovalViewModel()
      {
          Approvals = await _db.Approval.ToListAsync(),
         request = new Request()
  };
      return PartialView("_RequestHistory", model);
  }
  
  [HttpPost]
  [ValidateAntiForgeryToken]
  public async Task<IActionResult> History(RequestApprovalViewModel model)
  {
      var approvals = await _db.Approval
          .Include(c => c.Request)
          .Where(c => c.RequestId == model.request.Id).ToListAsync();
  
          return PartialView("_RequestHistory", approvals);
  }

  My RequestApprovalViewModel

   public class RequestApprovalViewModel
      {
          public Request request { get; set; }
          public virtual ICollection<Approval> Approvals { get; set; }
      }

  And Finally this is the partialView content

  @model IEnumerable<TestApplication.Models.ViewModels.RequestApprovalViewModel>
  
  @{
      ViewData["Title"] = "Requests";
  }
  
  <table class="table table-bordered table-striped datatable" id="table-3" dir="rtl">
      <thead>
          <tr>
              <th>  Seat number </th>
              <th>Request Date </th>
              <th> Approval Status  </th>
              <th> Approval Date   </th>
          </tr>
      </thead>
      <tbody>
  
          @foreach (var item in Model)
          {
              <tr>
  
                 <!-- Here where i should display a table of the approval history of the requst -->
              
              </tr>
          }
      </tbody>
  </table>

• • Reply
  jiadongm

  Participant

  1320 Points

  491 Posts

  Re: this ViewDataDictionary instance requires a model item of type 'System.Collections.Generic.IE...

  Jul 20, 2020 09:02 AM|jiadongm|LINK

  Hi ShahadAlshuhail,

  ShahadAlshuhail

  @await Html.PartialAsync("_RequestHistory", item)

  The problem is clear. Here, the item you pass to the partial view is type of Approval , while the partial view accpet a type of 

  IEnumerable<TestApplication.Models.ViewModels.RequestApprovalViewModel>

  You should change one of them to keep their types consistent.

  Best Regards,

  Jiadong Meng

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