angular, one of the most popular software development instruments and it is a part of the javascript ecosystem. it was introduced by google in the year 2009. according to survey by stackoverflow, 30.7 percent of software engineers apply angularjs ang the new version angular 2+ to create user interfaces.
an angular framework makes it easy to develop web applications. combining dependency injection, declarative templates, end-to-end tooling, and integrated best practices, it solves almost all the challenges when creating a web app.
the angular framework includes versions from 2 to 8. the 9th update was released in november 2019. in the section, we will elaborate on the improvements that each version of angular made.
angular 2: the release of angular 2 brought numerous changes to the initial framework, as it was rewritten in typescript. the architectural style switched to component-based.
angular 4: angular cli 1.0.0 was introduced with the fourth version, as a core element of the angular project. with the release of angular universal, angular applications could be rendered outside the browser.
angular 5-6: the release of fifth and sixth version concentrated on optimizing angular cli and compiler work.
angular 7: with angular 7 cli was enhanced with prompts which provided tips in cli to explain functions and purposes of elements. hence, using cli became more intuitive. applications received various improvements in the performance and size of the code-base.
angular 8: in this release, two elements were introduced ivy renderer, bazel(build interface). another major improvement is differential loading that is used to upload browser-specific bundles in order to support legacy browsers and upload content faster.
every technology comes with certain advantages and cons. in the section, we will take a closer look at these advantages and disadvantages of angular.
mvc architecture implementation
model-view-controller architecture, not only attaches value to the framework when creating a client-side app but also sets the foundation for the order features like data binding and scopes.
with mvc architecture, it is possible to isolate the app logic from the ui layer and support separation of concerns. the controller receives all requests for the app and operates with the model to prepare any data needed by the view. the view uses the data prepared by the controller and displays a final presentable response.
enhanced design architecture
some of the large web applications contain a lot of components. angular simplifies the way of managing these components event if a new programmer joins the project after the development process has already begun. the architecture is built in such a way that helps the programmer to locate and develp the code easily.
modules
a module is a mechanism that groups directives, components. pipes and services that are related, in such a way that can be combined with other modules in order to create an application the angular-based app can be considered as a puzzle where each module is needed to be able to see the full picture. there are a number of ways to add different elements to a module. angular solves the problem of global function exploitation by limiting the scope of all functions to the module, in which it was defined and used.
services and dependency injection(di)
a service or component might sometimes need other dependent services to complete a task. a dependency injection design pattern is used in order to fulfill these dependencies. it divides the task among different services. the client service will not create the dependent object, rather it will be created and injected by an angular injector. the angular injector is responsible for creating service instances and injecting them into classes like components and services.
custom directives
they improve html functionality and are suitable for dynamic client-side applications. thay all start with the prefix ng so html cal identity them. some o these are:
ngmodel: provides two-way data binding to an html form elements.
ngclass: removes and adds a set of css classes.
ngstyle: adds and removes a set of html styles.
typescript: better tooling, cleaner code, and higher scalability
angular is wirtten using typescript, which is superset for javascipt. it fully compiles to javascript and also helps spot and eliminate common mistakes while coding. while small javascript projects do not require such an enhancement, the enterprise-scale applications need developers to make their code cleaner and verify the quality more often.
limited seo options
a major drawback of using angular is the limited seo options and poor accessibility for search engine crawlers.
angular is verbose and complex
a frequent complaint that you would hear from the angular developers is the verbosity of the instrument. and this problem hasn't changed much since angularjs.
steep learning curve
if you onboard new developers who are familiar with javascript to use new angular, they would find it difficult as compared to react or vue onboarding. this is because the array of topics and aspects to be covered is quite large.
cli documentation is lacking details
some developers express concerns with the current state of cli documentation. while the command line is very useful to angular developers, you won't find enough information in their official documention on github and you have to spend more time exploring threads on github to get answers.
although the platform has its share of cons, angular is a full-featured and dynamic framework. and its usability, flexibility, and maintainability makes it unique and provides chances to create excellent and successful web-based applications.
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