.NET core MVC that uses the EF Framework - Pass the data from one controller another

Question

I am doing the first time Web App development using the ASP.NET Core MVC with the EF. I have two tables Customer and Inventory in the SQL Server database.

I did the Scaffold-DbContext and generated the models/controllers and views for both the tables. My requirement is that from the Customer index page on the each customer on the grid I added a select button, when this select button is clicked I need to pass the selected customer data to the inventory controller and show the customer select on top of the inventory index page and below I showing the grid with the inventory table.

I am using TempData here. On the customer table I added the select button

<td>
    <a asp-action="passToInventory" asp-route-id="@item.CustomerId">Select</a>
</td>

CustomersController:

public async Task<IActionResult> passToInventory(int? id)
{
    if (id == null)
    {
        return NotFound();
    }

    Customer customer_data = await _context.Customers.FindAsync(id);

    TempData["custdata"] = customer_data;

    return RedirectToAction("Index", "Inventories");
}

Now on the InventoriesController in the Index method, I made the change like to access the TempData passed

public async Task<IActionResult> Index()
{
    Customer cust_data = TempData["custdata"] as Customer;
    return View(await _context.Inventories.ToListAsync());
}

I tried to create a model class so I can use both the customer and the inventory list on the Inventory Index page like below:

public class CustomerInventoryCollectionDataModel
{
    public Customer CustomerData { get; set; }
    public List<Inventory> Inventorys { get; set; }
}

I couldn't get the data retrieved on the Index page of the Inventory

 @model IEnumerable<JAXSurplusMouseApp.Models.CustomerInventoryCollectionDataModel>
  
//show the selected customer data from the previous page 
  unable to access the customer data here and show it 

//table for the Inventory list 
<tbody>
    @foreach (var item in Model)
    {
        <tr>
            <td>
                @Html.DisplayFor(modelItem => item.Inventorys.QuantityAvailable)
            </td>
         </tr>
     }

Please suggest how I can retrieve both the models in the same view and show them in the same page. Any help is greatly appreciated

Answer 1

action

public async Task<IActionResult> Index()
 {
  Customer custData = TempData["custdata"] as Customer;
  var inventories =await _context.Inventories.ToListAsync();
  var model= new CustomerInventoryCollectionDataModel
{
   CustomerData = custData,
    Inventorys =inventories 
};

  return View(model);
 }

view

@model JAXSurplusMouseApp.Models.CustomerInventoryCollectionDataModel
  
//show the selected customer data from the previous page 
//  using  @Model.CustData
 
@Html.DisplayFor(model => model.CustData.Name)

....and so on

//table for the Inventory list 
<tbody>
    @foreach (var item in Model.Inventorys)
    {
        <tr>
            <td>
                @Html.DisplayFor(modelItem => item.QuantityAvailable)
            </td>
         </tr>
     }

but I am afraid you will need to serialize customer , so it seems more efficient for me to use this

public async Task<IActionResult> passToInventory(int? id)
 {
   if (id == null)
   {
     return NotFound();
   }
  
   return RedirectToAction("Index", "Inventories",new { id });

 }

action

public async Task<IActionResult> Index(int? id)
 {
 if(id==null) return ...error

  Customer custData =   await _context.Customers.FindAsync(id);
  var inventories =await _context.Inventories.ToListAsync();
  var model= new CustomerInventoryCollectionDataModel
{
   CustomerData = custData,
    Inventorys =inventories 
};

  return View(model);
 }

or if you need to use TempData customer for some reason, you can use this in the code

var customerData = await _context.Customers.FindAsync(id);

TempData["custdata"] =
System.Text.Json.JsonSerializer.Serialize( customerData;)

//index
 Customer custData = System.Text.Json.JsonSerializer.Deserialize<Customer> ( 
TempData["custdata"].ToString());

PS

I don't know maybe you have more code in passToInventory action then it is posted, but the way it looks now IMHO you could go immediately to index

<td>
 <a asp-action="Index" asp-controller="Inventories" asp-route-id="@item.CustomerId">Select</a>
</td>