MVC3/4/5/6 layout page and razor syntax

I. Directory structure

Second, Razor grammar

Code block: @{}, such as: @{html.raw ("");}

@if () {}

@switch () {}

@for () {}

@foreach () {}

@while () {}

@do {}while () {}

The statement in the code block ends with a semicolon

Expression or variable: start at @, such as: @User. Name or @ (User.Name + "welcome You"), @ ()

Variables can be declared by Var and can only be in blocks of code, such as: @{var abc= "AAA";}

Method invocation: Starts at @, such as: @Html. Encode ("")

Single-line text output: @: Directly after output text

Multiline text output: Use any label <span> text content </span>

e-Mail can be automatically identified:[email protected]

If you mistakenly believe that the mailbox can be [email protected] (UserName)

Output @ symbol: @@ 会 output an @ character

Third, layout page

~/views/_viewstart.cshtml is the page that will be referenced when all view pages (without a partial attempt page) are started, with the default layout page address:

" ~/views/shared/_layout.cshtml ";

~/views/shared/_layout.cshtml is the default layout page for the entire project:

<! DOCTYPE html>"Utf-8"/> <meta name="Viewport"Content="Width=device-width"/> <title> @ViewBag .title</title>    @* Load css*@ @RenderPage ("~/views/shared/_css.cshtml")    @* Custom CSS: Can be selected by the content page to fill *@ @RenderSection ("Customcss")    @* Custom Header JS: Can be filled by the content page self-selection *@ @RenderSection ("Customjs_header",false)    @* Load header*@ @RenderPage ("~/views/shared/_header.cshtml")    @* Load Body content page fill content *@ @RenderBody () @* Load footer*@ @RenderPage ("~/views/shared/_footer.cshtml")    @* Load js*@ @RenderPage ("~/views/shared/_js.cshtml")    @* Custom Foot JS: Can be filled by the content page self-selection *@ @RenderSection ("Customjs_footer",false)    @* Determine if the content page has rendered this node, if rendered, does not show default *@ @if (issectiondefined ("replaceablecontent") {@RenderSection ("replaceablecontent")    }    Else    {            }</body>
Renderpage ("page address"): Renders the contents of a page, typically used to load headers and footers
Rendersection ("node name", whether the content page must be rendered): Defines a node that the content page chooses to render
Renderbody (): All content on the content page is rendered to this location, equivalent to a placeholder for a content page
Issectiondefined: Checks whether the content page has already rendered this node, is the node that renders the content page, and no displays the default
MVC sets the name of a file that begins with an underscore by using the Web to request browsing individually, as follows:
_layout.cshtml
_header.cshtml
_footer.cshtml
Root directory: "~" represents the program root directory, such as: View ("~/views/home/about.cshtml");
Four, view page
@{Viewbag.title="Index"; //Layout = null;//each page can specify a layout page individually} @using System.Data.Common @model system.string@section customcss{<style>Div {height:20px;        margin:10px 10px 10px 10px; }    </style>} @section customjs_header{<script type="Text/javascript">(function Testheaderfun () {Console.log ("Js_header");    })(); </script>} @section customjs_footer{<script type="Text/javascript">(function Testfooterfun () {Console.log ("Js_footer");    })(); </script>}<div style="border:1px Solid Purple">I'm the body @Model. Length @{Html.raw ("");} @{Html.renderaction ("actionpartial","Home");} @{html.renderpartial ("viewpartial");} @Html. Action ("actionpartial","Home") @Html. Partial ("viewpartial")</div>
The Layout property can define whether the current page has a reference layout page null is not referenced, or can be defined to refer to other layout pages: layout = "~/views/shared/_layout_nologin.cshtml";
Introducing namespaces with using using: @using System.Data.Common
Sets the data type of return View ("") returned by the action: @model
The page is capitalized with the @Model first letter: @Model
Implement custom nodes for layout pages: @section node name {} such as: @section customcss{}
Output HTML content: The default MVC is to encode HTML tags in order to prevent XSS attacks if you want to output tags using @html.raw ("")
Introduce a partial attempt:
1, need to request the background action: (Action can be added childactiononly tag to prevent independent access)
@Html. Action ("Actionpartial", "Home")
@{html.renderaction ("Actionpartial", "Home");}
2. Load View directly
@Html. Partial ("Viewpartial")
@{html.renderpartial ("viewpartial");}
The difference between the two is that the former return mvchtmlstring object in the parsing to the current page, directly call, the latter directly to the content output to TextWriter, need code block call, theoretically the latter less than the former conversion should be slightly better performance, but this is too small.
V. Other
MVC also has three ways to interact with data
ViewData: The dictionary type (Dictionary), which passes the data by action to the view, the life cycle only in the current view, with the viewdata["Key" mode to access the value, for manual conversion type;
ViewBag: Dynamic type, which passes data by action to view, life cycle only in current view, Viewbag.key to access values, for no conversion type, underlying nature or viewdata only more layer dynamic control;
TempData: Dictionary type (Dictionary), you can pass data in any action and view, the life cycle is automatically deleted after the call, to tmpdata["Key"] mode to access the value, for manual conversion type;
Razor IntelliSense:
In the cshtml page after the smart prompt, if we define a class, and in view want to intelligently prompt this class of information, in the View/web.config file, open will find the following node:
<system.web.webPages.razor> "System.Web.Mvc.MvcWebRazorHostFactory, SYSTEM.WEB.MVC, version=4.0.0.0, Culture=neutral, publickeytoken= 31bf3856ad364e35"/> <pages pagebasetype="System.Web.Mvc.WebViewPage"> <namespaces> <addnamespace="SYSTEM.WEB.MVC"/> <addnamespace="System.Web.Mvc.Ajax"/> <addnamespace="System.Web.Mvc.Html"/> <addnamespace="System.Web.Optimization"/> <addnamespace="System.Web.Routing"/> </namespaces> </pages> </system.web.webPages.razor>
Simply add the namespace of the class you want to use, just like using it;
OutputCache output cache:
By using the OutputCache feature, we implemented a cache of objects. Therefore, when duplicate requests occur, it is possible to automatically output cache information to avoid querying the database frequently, reduce the burden on the server and improve the response speed.
[HttpGet]//set allow only get or post requests PublicActionResult Index (intID) {viewdata["ID"] =ID; Viewbag.id=ID; tempdata["ID"] =ID; returnView (String.Empty);} [OutputCache (Duration= -)]//setting the page output cache[Childactiononly]//defining this action can only be called by a child action PublicActionResult actionpartial () {returnPartialview ();}
MVC3/4/5/6 layout page and razor syntax