Setting properties using asp-for in MVC Core App with EF Core? - asp.net-core

Question

As I understand it from these docs: https://learn.microsoft.com/en-us/aspnet/core/mvc/views/tag-helpers/intro?view=aspnetcore-3.1 , asp-for is used to transfer values from input elements to backend C# class properties, for example:
<input type="text" id="wsite" name="wsite" maxlength="11" asp-for="WebsiteName">
Along with '#folderName ClassName;' at the top, lets you transfer to this example property:
public string WebsiteName { get; set; }
However, testing this out with console.WriteLine show that the property is still null after the form containing the input has been submitted. Any idea what I'm missing?
Edit: Updated to show my property name and asp-for value match, and to add my controller:
[HttpPost]
public IActionResult Post()
{
DBCRUD.Initialize(_context);
return NoContent();
}

Answer 1

The asp-for tag should match the variable-name.
Try defining your html-form like:
#model Classname
<form asp-action="ActionName" asp-controller="ControllerName" ...>
<input type="text" asp-for="VarName">
and your controller:
public MyReturnVariable ActionName(ClassName class) {
Console.WriteLine(class.VarName);
}

Answer 2

The Tag Helpers is used with Model binding and creating and rendering HTML elements(display the model properties) in the web page.
So, in the Web page (or view page), at the top of the header, we should add the following code to assign the model.
#model MVCSample.Models.BookModel
Then, using the following code to display the properties:
<div class="row">
<div class="col-md-4">
<form asp-action="AddBook">
<div asp-validation-summary="ModelOnly" class="text-danger"></div>
<div class="form-group">
<label asp-for="ID" class="control-label"></label>
<input asp-for="ID" class="form-control" />
<span asp-validation-for="ID" class="text-danger"></span>
</div>
<div class="form-group">
<label asp-for="bookName" class="control-label"></label>
<input asp-for="bookName" class="form-control" />
<span asp-validation-for="bookName" class="text-danger"></span>
</div>
<div class="form-group">
<label asp-for="Title" class="control-label"></label>
<input asp-for="Title" class="form-control" />
<span asp-validation-for="Title" class="text-danger"></span>
</div>
<div class="form-group">
<input type="submit" value="Create" class="btn btn-primary" />
</div>
</form>
</div>
</div>
Code in the controller:
[HttpGet]
public IActionResult AddBook()
{
BookModel book = new BookModel()
{
ID = 1001,
bookName = "War and Peace",
Title = "War and Peace"
};
return View(book);
}
Code in the model:
public class BookModel
{
public int ID { get; set; }
public string bookName { get; set; }
public string Title { get; set; }
}
More details information, you could check the Model Binding.