如何从不同的控制器在视图中显示计数

Question

I changed the Person controller and Home view.
I have 209 people in the database. And that's how it shows me in the Person view.
When I interrupt the code count shows me 0.

View Home: I also made changes here.

 @model Legolandia.Models.Store    
    @{    
        ViewBag.Title = "Home Page";
    }

    <div class="jumbotron">

    <div class="row">
     @section Scripts {
    <script>
// document.ready is fired once the page has loaded in the browser
$(document).ready(function () {
    // set the url to get the data from the PersonController
    var url = '@Url.Action("GetPersonCount", "Person")';

    // use jQuery.getJSON to get our data from the controller
    $.getJSON(url, function(data) {
        // update the element with the count from the controller
        $('#personCount').text(data.count);
    });
});
    </script>
}
        <div id="orange" class="col-md-4">
            <a class="change-a" href="/Person/Index">

                <div class="change-title">
                  Person in system: <span id="personCount"></span>
                </div>

Controller Person:

I also made changes here.

  using System;
    using System.Collections.Generic;
    using System.Data;
    using System.Data.Entity;
    using System.Linq;
    using System.Net;
    using System.Web;
    using System.Web.Mvc;
    using Legolandia.Models;

    namespace Legolandia.Controllers
    {
        public class PersonController : Controller
        {
            private LegolandEntities db = new LegolandEntities();

            // GET: Person  

            public ActionResult Index()
            {
                var person = db.Person.Include(o => o.xxx);
                ViewBag.PersonCount = db.Person.Count();
                return View(person.ToList());
            }

   public ActionResult GetPersonCount()
        {
            var count = db.Person.Count();  // get count from database
            var data = new { count };       // anonymous type
            return Json(data);              // return serialized Json data
        }

Answer 1

Since you need to get data from PersonController and display it in a view of HomeController , I'd suggest using Ajax.

Create a new method in PersonController to return the data you need. This method will return Json data which you can use in the view.

public ActionResult GetPersonCount()
{
    var count = db.Person.Count();  // get count from database
    var data = new { count };       // anonymous type
    return Json(data, JsonRequestBehavior.AllowGet);  // return serialized Json data
}

Note: If you're using .Net Core you don't need the JsonRequestBehavior.AllowGet in the Json result.

Now, in Home/Index.cshml you will need to add some JavaScript. I'll actually use jQuery since it makes this task a little easier. Make sure you include jQuery on the page (MVC comes with jQuery included these days).

First, in Home/index.cshtml create a <span> element which will hold the value for PersonCount :

<div class="change-title">
    Person in system: <span id="personCount"></span>
</div>

Now, near the bottom of Home/index.cshtml add some script tags:

@section Scripts {
<script>
    // document.ready is fired once the page has loaded in the browser
    $(document).ready(function () {
        // set the url to get the data from the PersonController
        var url = '@Url.Action("GetPersonCount", "Person")';

        // use jQuery.getJSON to get our data from the controller
        $.getJSON(url, function(data) {
            // update the element with the count from the controller
            $('#personCount').text(data.count);
        });
    });
</script>
}

Finally, in _Layout.cshtml make sure you put @RenderSection("Scripts", required: false) near the bottom of the page (below @RenderBody() ).

Here I have used $.getJSON . It performs an ajax request to Person/GetPersonCount . Then we update the <span> with the person count from the GetPersonCount in PersonController .

Here's the result:

Answer 2

这种方法对我有用：

ViewBag.PatientCount = (from x in Hasta.TblPatient select x).Count();

Answer 3

In your controller, save count in ViewData :

{
   ViewData["Users"] = _userManager.Users.Count();
   
   return View();
}

In your view, retrieve the value:

@Html.ViewData["Users"]