I'm upgrading from .NET 2.0 to MVC 4. Back in .NET 2.0 webform, we had to inject license information on the fly to the footer of the software by override the "Render" function in .aspx.cs page (using HtmlTextWriter), find a particular spot of the footer and then insert the license text info there.
The reason I don't want to directly put that in the viewstart page or any razor page themselves using HTMLhelper is because I don't want my customers to mess with it. So hard code is not an option.
I use Glimpse and I see Glimpse is enabled by adding a HTTPModule,etc in web.config and magically, an icon appears on my app. Something similar ?
Bottom line is, I need to hijack the finished HTML output, modify it and return the final result to client.
How do you do this in MVC? HttpModule?
Thanks!
Glimpse uses a feature of ASP.NET called a ResponseFilter to change the output HTML on the fly.
The ResponseFilter, in the case of Glimpse, is set inside the HttpModule - but it could be set anywhere.
Four Guys From Rolla has an old but still relevant article on how to create ResonseFilters.
Related
When you add Identity to your ASP.NET Core applications, you can scaffold its Razor pages.
I am looking for a way to extract my views from a referenced RCL just like Identity.
I mean I want to create Area and related files (cshtml) to help developers to customize it (not a specific UI as you see in the above pic).
Do there exist any command-line tools to a way to extract Razor pages (.cshtml)?
I checked inside of a Razor class library with dotpeek there is no HTML resource, everything is class.
Any idea?
Is it best practice for ALL text on a .Net Core Razor webpage to be injected with Model Binding (Even on a static page), or should I only inject text which may need to change dynamically at runtime?
E.g. My Index.cshtml page has a h1 title as per below. Is this considered bad practice or is it ok?
<h1 class="block-title-text" localize-content>A Fun Title</h1>
Thanks. Just trying to get my head around Razor and .Net Core.
This if fine, in general you should keep user interface elements in the view (or the .cshtml file for Razor Pages). See benefits of using views for more details, which among other things includes:
The parts of the app are loosely coupled. You can build and update the app's views separately from the business logic and data access components. You can modify the views of the app without necessarily having to update other parts of the app.
Just realised something which is obvious in hindsight. By injecting the strings using Model Binding instead of placing them into the HTML as above, it allows the incorporation of unit tests around those strings.
I'm probably just missing a simple trick here, but I created the Identity framework in an ASP.NET Core project, created my own fields with my own classes, ran migrations, then once confirmed it was all working with the Default UI. It was working perfectly so went to customize the Identity UI so I could better control specific pages. Trouble was, thought I'd be adventurous and select every page to customize... yes dumb I know.. Now I've got some 80 pages or something that I no longer want.
I really only want to scaffold the registration and manage data pages, if I ran the Scaffolding again will that simply create new pages or fail because the pages already exist, or will it remove any pages that I don't select? I'm loathed to try it for fear of breaking something.
Perhaps it's down to manually deleting the pages I don't want, but will that cause issues with those pages that I haven't selected to customize. Seems great there's a scaffolding option to create the pages, but removing them... it's not so obvious...
For removing unwanted Identity Pages, you could delete them directly from your solution.
For Identity Razor page, if you add scaffold pages or manually create the razor pages with the corresponding name in Identity/Pages/Account, they will replace default Identity Razor page implementation. If there is no razor pages or you delete them, it will reuse default razor page from Razor library.
When I create a web project using "ASP.NET Core Web Application" / "Web Application" (non-MVC) / "Individual User Accounts"... I get the sample project with Register and Login buttons that show their respective pages when I click on them. HOWEVER... the very weird thing is if I search for "Create a new account" which is on the register page it's not found... and more... there is no AccountController in the Identity area or anywhere... so 1) the pages aren't anywhere in my solution folder and 2) how in the world are these pages showing up?!? I've tried on two different computers now. (using Core 2.1)
As an example this link works:
<a asp-area="Identity" asp-page="/Account/Login">Login</a>
and takes me to:
https://localhost:44300/Identity/Account/Login
and yet my folder structure (both in the solution and on disk) looks like this:
ASP.NET Core 2.1 with Identity automatically includes the "Default UI". It's a Razor Pages class library that's referenced via AddDefaultIdentity in Startup, which under the hood literally calls AddDefaultUI.
If you want the actual files in your project, you need to scaffold them in. Right click your project in the solution explorer and choose Add > New Scaffolded Item... Then, click the Identity listing on the left, and then the Add button. A new window will pop allowing you to select the pages you want included, your context, etc. Configure it how you like and go.
It's also worth noting, that as long as you use AddDefaultIdentity, the default UI is still included, which means you don't actually need all the scaffolded files if you want any of them. They'll essentially function as overrides. Anything specifically included in your project will be used, while anything that's missing will be pulled from the default UI.
This also means that if you want to do something like use standard controller actions and views instead of Razor Pages, the default UI will still be active, and take precedence. You have to use AddIdentity or AddIdentityCore instead of AddDefaultIdentity if you want the default UI off completely.
ASP.NET Core 2.1 introduced Razor UI in class libraries. Identity with it's UI is in nuget package.
The nice thing about this is you can now package UI with your libraries and then expose the UI for overriding.
This post describes how to override the UI. Essentially, you add the pages you want to override to your project to /Areas/Identity/Pages.... the easiest way currently is to run the scaffolder for identity and a visual walkthrough.
I'm new to web development and ASP.NET MVC 4
My question is: Is it possible to replace the content of div tag without needing to refresh the whole page?
If so, what is the best practice of it (best use of MVC 4)?
In order to refresh partial content of a page, you have to use AJAX. There are plenty of resources available online describing how to implement this in ASP.NET MVC. One of the possibilities is using partial views, on which you can find a good tutorial here. However, if you're comfortable with javascript/jQuery a partial view might be overkill if you're just looking to update one div.
Use javascript and make an ajax call. MVC has a JsonResult for the controller you can use if you like.
Not 100% sure but if I remember right, jQuery is bundled with MVC4. Correct me if I'm wrong.
// Javascript code
$('#mydiv').load('/Content/html/mySnippet.html');
Would replace the contents of a <div id="mydiv"></div> with the contents of the /Content/html/mySnippet.html.
You can also call an action and return a partial view if you wish to have dynamic content instead of a static html template.