What is a Razor view and how do you use it in ASP.NET Core?

A Razor view is a template-based view engine in ASP.NET Core that uses the Razor syntax to generate HTML markup. Razor views are used to define the user interface of an application and can be used to display dynamic content based on data provided by the controller.

To use a Razor view in an ASP.NET Core application, you first need to create a view file with the .cshtml file extension. Views are typically stored in the Views folder in your application and organized into subfolders based on the corresponding controller. For example, a view for the Index action of the HomeController would typically be located at Views/Home/Index.cshtml.

Here's an example of a simple Razor view:

@model MyNamespace.Models.MyModel

<h1>Welcome to my application!</h1>

<p>Hello, @Model.Name!</p>

<ul>
@foreach (var item in Model.Items)
{
    <li>@item</li>
}
</ul>
 

 

In this example, the @model directive is used to specify the model type for the view. The model type is typically a class that defines the data that will be displayed in the view. The @Model keyword is then used to access properties of the model within the view.

The Razor syntax is used to generate HTML markup and control the flow of the view. For example, the @foreach statement is used to loop over items in a collection and generate HTML markup for each item.

To render a Razor view in an action method of a controller, you can use the View method:

 public IActionResult Index()
{
    var model = new MyModel
    {
        Name = "John",
        Items = new List<string> { "Item 1", "Item 2", "Item 3" }
    };

    return View(model);
}

In this example, the View method is used to return a view with a model of type MyModel. The view engine will automatically locate the view file based on the naming convention and folder structure, and generate HTML markup based on the Razor syntax and model data.

You can also use layouts and partial views to define reusable portions of the user interface, and render them within your Razor views using the @layout and @partial directives, respectively.