Html.Partial vs Html.RenderPartial & Html.Action vs Html.RenderAction

HTML.Partial vs. HTML.RenderPartial and HTML.Action vs. HTML.RenderAction: A Comprehensive Comparison

When working with ASP.NET MVC or ASP.NET Core MVC, developers often encounter scenarios where they need to include reusable components or partial views within their web applications. Two commonly used methods for achieving this are Html.Partial and Html.RenderPartial, as well as Html.Action and Html.RenderAction. In this article, we’ll delve into the differences between these methods, their use cases, and when to choose one over the other.

HTML.Partial vs. HTML.RenderPartial

HTML.Partial:

Html.Partial is a method used to render a partial view as part of the parent view’s rendering process. It returns the HTML content of the partial view as a MvcHtmlString, which can be included in the parent view.

Here’s how you can use Html.Partial in a Razor view:

@Html.Partial("_PartialViewName")

HTML.RenderPartial:

Html.RenderPartial, on the other hand, is used to render a partial view directly to the response output stream. It doesn’t return a value; instead, it writes the HTML content directly to the response.

Here’s how you can use Html.RenderPartial in a Razor view:

@{ Html.RenderPartial("_PartialViewName"); }

Key Differences:

1. Return Type:
   • Html.Partial returns a MvcHtmlString, which you can assign to a variable or use within your view as needed.
   • Html.RenderPartial doesn’t return a value; it directly writes the HTML to the output stream.
2. Usage:
   • Use Html.Partial when you need to capture the HTML content of a partial view and use it within your view or assign it to a variable for further manipulation.
   • Use Html.RenderPartial when you want to include a partial view in your page directly without any additional manipulation.
3. Performance:
   • Html.RenderPartial is generally more efficient in terms of performance because it writes directly to the response stream and doesn’t require creating an intermediate MvcHtmlString object.

HTML.Action vs. HTML.RenderAction

HTML.Action:

Html.Action is used to invoke a child action method within your view and capture its rendered output as a MvcHtmlString. It is commonly used when you want to execute a separate action method and include its result within your view.

Here’s how you can use Html.Action in a Razor view:

@Html.Action("ActionName", "ControllerName")

HTML.RenderAction:

Html.RenderAction is similar to Html.Action, but instead of returning a value, it directly writes the result of the child action method to the response output stream.

Here’s how you can use Html.RenderAction in a Razor view:

@{ Html.RenderAction("ActionName", "ControllerName"); }

Key Differences:

1. Return Type:
   • Html.Action returns a MvcHtmlString, allowing you to capture and manipulate the rendered output.
   • Html.RenderAction doesn’t return a value; it writes the output directly to the response stream.
2. Usage:
   • Use Html.Action when you need to execute a separate action method, capture its output, and use it within your view.
   • Use Html.RenderAction when you want to include the result of a child action method directly in your page without any additional manipulation.
3. Performance:
   • Html.RenderAction is generally more efficient in terms of performance because it writes directly to the response stream, similar to Html.RenderPartial.

Choosing Between Them:

The choice between Html.Partial/Html.RenderPartial and Html.Action/Html.RenderAction depends on your specific use case:

• Use Html.Partial or Html.RenderPartial when you want to include a reusable piece of HTML content (partial view) directly within your view or capture its output for further manipulation.
• Use Html.Action or Html.RenderAction when you need to invoke a separate action method, execute logic within that action, and include the resulting HTML within your view.
• Consider performance implications when making your choice. If you need the best performance and don’t require capturing the output, Html.RenderPartial or Html.RenderAction is a better choice.

In conclusion, Html.Partial, Html.RenderPartial, Html.Action, and Html.RenderAction are valuable tools for rendering partial views and executing child action methods in ASP.NET MVC and ASP.NET Core MVC applications. Your choice should be based on your specific requirements, including whether you need to capture the output, and performance considerations for your application.