Pass parameter (a list object) from View (List type) to Controller. Asp.NET MVC

Question

I own a view like "List<SimpleUser>" and I want to pass by parameter to my controller the object that is in my foreach, but this arriving null being done as follows:

View:

@{
    ViewBag.Title = "Dashboard";
}

<!-- search form -->
<form action="#" method="get" class="sidebar-form">
    <div class="input-group">
        <input type="text" name="q" class="form-control" placeholder="Buscar entre seus clientes/pacientes..." />
        <span class="input-group-btn">
            <button type='submit' name='seach' id='search-btn' class="btn btn-flat"><i class="fa fa-search"></i></button>            
        </span>
    </div>
</form>

@if (Model.Count() > 0)
{
    foreach (var sUser in Model)
    {
        <div>            
            @Html.ActionLink(@sUser.Name, "ClientDetails", "ProfessionalUserHasClient", new { simpleUser = sUser })
        </div>
    }
}
else
{
    <label>Você não tem clientes/pacientes vinculados.</label>
}

Controller:

public ActionResult ClientDetails(SimpleUser simpleUser)
{
    SimpleUser sUser = ViewBag.SimpleUser as SimpleUser;
    return View();
}

Change to @Html.Action(), it passes perfectly but is carried inside the View, an entire part of the layout, which obviously should not be loaded, follows a print of how it would look:

Answer 1

Don’t go through the ActionLink the whole object. Pass only the Id of the object. Do the Binding of an entire object is very laborious and has a good chance of not working.

Change:

@Html.ActionLink(@sUser.Name, "ClientDetails", "ProfessionalUserHasClient", new { simpleUser = sUser })

For:

@Html.ActionLink(@sUser.Name, "ClientDetails", "ProfessionalUserHasClient", new { id = sUser.Id }, null)

Don’t forget the null in the end, or you’ll fall into overload wrong of ActionLink.

You will have to load the data again. There will be no way.

To Action gets like this:

public ActionResult ClientDetails(int id)
{
    var sUser = context.SimpleUsers.SingleOrDefault(su => su.Id == id);
    return View(sUser);
}

I don’t understand the part where you upload the data and don’t send it to View. I imagine that Model next View be loaded with the instructions of Action. Therefore:

return View(sUser);

Send the uploaded data to View.

Answer 2

Explanation:

In a @Html.ActionLink an element is returned a which in case would be <a href=""></a>, so such instruction does not work, returning a complex data in this case will not take effect, while in a @Html.Action an output is returned in HTML, and executed in the case of a Controller and Action, including complex data (class, object) or primitive types, having a rendering as said of a HTML, as in your questioning has such execution.

So it’s different things having other results. By default when using @Html.ActionLink is passed in your a, an identification of the record (Id for example, identifying such a line), example:

1) @Html.Actionlink

Na View:

@if (Model.Count() > 0)
{
    foreach (var sUser in Model)
    {
        <div>            
            @Html.ActionLink(@sUser.Name, "ClientDetails", "ProfessionalUserHasClient", new { Id = sUser.Id }, null)
        </div>
    }
}

In Action:

public ActionResult ClientDetails(int? Id)
{
    //recupera o Id
    return View();
}

---

2) @Html.Action

It is used to load in the case Partialview and very useful for this, ie fragments of pages loaded in existing layout, with features for example caching to increase performance, decreasing traffic in the network.

Na View

@Html.Action("Menu", "Home")

In Action

public PartialViewResult Menu()
{
    return PartialView("Menu");
}