Html.Partial and Html.RenderPartial
The Html.Partial helpers renders a partial view in to string.You can reuse this Partial Views in Multiple Views. Partial has four overloads
public void Partial(string partialViewName);
public void Partial(string partialViewName, object model);
public void Partial(string partialViewName, ViewDataDictionary viewData);public void Partial(string partialViewName, object model,ViewDataDictionary viewData);@Html.Partial("MyPartial")RenderPartial writes directly to the response output stream instead of returning a string. So, you should place RenderPartial inside a code block instead of a code expression
@{Html.RenderPartial("MyRenderPartial");}So, which should you use, Partial or RenderPartial?
In general, you should prefer Partial to RenderPartial because Partial is more convenient (you don’t have to wrap the call in a code block with curly braces). However, RenderPartial may result in better performance because it writes directly to the response stream.
Html.Action and Html.RenderAction
Example :
Imagine you are using the following controller
public class ActionDemoController : Controller {
public ActionResult Index() {
return View();
}
[ChildActionOnly]
public ActionResult DisplayMenu() {
var menu = GetMenuFromSomewhere();
return PartialView(menu);
}
}
The Menu action builds a menu model and returns a partial view with just the menu:
@model Menu
<ul>
@foreach (var item in Model.MenuItem) {
<li>@item.Text</li>
}
</ul>
In your Index.cshtml view, you can now call into the Menu action to display the menu:
<html>
<head><title>Index with Menu</title></head>
<body>
@Html.Action("DisplayMenu")
<h1>Welcome to the Index View</h1>
</body>
</html>
Notice that the Menu action is marked with a ChildActionOnlyAttribute. The attribute prevents the runtime from invoking the action directly via a URL. Instead, only a call to Action or RenderAction can invoke a child action. The ChildActionOnlyAttribute isn’t required, but is generally recommended for child actions.
Passing values to Action
Sometimes you want to pass parameters in to the action.
Example:
[ChildActionOnly]
public ActionResult Menu(MenuParameters param) {
return PartialView(param);
}
@Html.Action(“Menu”, new {options = new MenuParameters { Width=400, Height=500 } })
Enjoy Coding…
