When you first time learn ASP.NET you should learn ASP.NET syntax (ASMX), HTML, C#, and JavaScript on Windows Platform. When you learn ASP.NET MVC you should learn HTML, C# and JavaScript on Windows Platform. When you learn ASP.NET Core you should learn HTML, C#, and JavaScript on any platform. Blazor is a ASP.NET feature that give you a power to build dynamic web app with HTML and C# on any platform. You do not need JavaScript although it can communicate flawlessly with JavaScript.
Blazor Template
You have two templates. Blazor Server App that run just like traditional server-side application. Blazor WebAssembly App that work just like client-side application that can work just like JavaScript, Progressive Web App, and ASP.NET hosted. You can see the difference here.
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What should I Use?
Use Blazor Web App if you want to create web application that run on the client side. Building web app for your customer, blogs, or might be an information system without real time communication. Use Blazor WebAssembly App if you want the web application that can run in the server and doing real time communication such as IM platform, High performance web app, and complex information system such as E-learning, E-commerce, etc.
Blazor Server App.
Blazor faster enough if you compare it with ASP.NET MVC and ASP.NET Webforms.
It quite simple in term of structure.
The shared folder consists of main layout (master page) and navigation. The pages consist of the page of each function of sample. It uses the razor syntax on asp.net pages.
Communicating with the services or data quite simple. They just need a entity class just like ASP.NET core and service call model.
And you just need to call like
Is it worthen?
If you come from asp.net MVC. Blazor will give you so much simplicity and better performance.
If you come from asp.net Web Forms. Blazor will give you short learning curve and best performance.
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