In this article I will explain with an example, how to Post JSON to Controller without AJAX in ASP.Net Core (.Net Core 8) MVC.
Note: For beginners in ASP.Net Core (.Net Core 8) MVC, please refer my article ASP.Net Core 8: Hello World Tutorial with Sample Program example.
 
 

Installing Newtonsoft package using Nuget

In order to install Newtonsoft library using Nuget, please refer my article Installing Newtonsoft library using Nuget.
 
 

Model

The Model class consists of following properties.
public class PersonModel
{
    /// <summary>
    /// Gets or sets Name.
    /// </summary>
    public string Name { get; set; }
 
    /// <summary>
    /// Gets or sets Age.
    /// </summary>
    public int Age { get; set; }
}
 
 

Namespaces

You will need to import the following namespaces.
using Newtonsoft.Json;
 
 

Controller

The Controller consists of following Action methods.

Action method for handling GET operation

Inside this Action method, simply the View is returned.
 

Action method for handling POST operation

Inside this Action method, the received JSON string is deserialized into a PersonModel object.
Finally, user is redirect to the Index method.
public class HomeController : Controller
{
    // GET: Home
    public IActionResult Index()
    {
        return View();
    }
 
    [HttpPost]
    public IActionResult Index(string json)
    {
        PersonModel personModel = JsonConvert.DeserializeObject<PersonModel>(json);
        return RedirectToAction("Index");
    }
}
 
 

View

HTML Markup

The View consists of a Form with an HiddenField and a Button.
The Button has been assigned with a JavaScript onclick event handler.
 
Inside the View, following jQuery file is inherited.
1. jquery.min.js
 

JavaScript Implementation

Inside the Save JavaScript function, a JSON object is created and Name and Age values are assigned.
Then the JSON object is converted into string using JSON.stringify function and stored into the Hidden Field.
Finally, the Form is submitted which sends the JSON string to the Controller.
@{
    Layout = null;
}
 
<!DOCTYPE html>
 
<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>Index</title>
</head>
<body>
    <form method="post" asp-controller="Home" asp-action="Index">
        <input type="hidden" name="json" value="" />
        <input type="button" value="Save" onclick="Save()" />
    </form>
    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
    <script type="text/javascript">
        function Save() {
            var person = {};
            person.Name = "Mudassar Khan";
            person.Age = 40;
            $("[name=json]").val(JSON.stringify(person));
            document.forms[0].submit();
        }
    </script>
</body>
</html>
 
 

Screenshot

ASP.Net Core: POST JSON to Controller without AJAX
 
 

Downloads

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