How to Upgrade from Angular 2 to Angular 5 Apps
This blog represents steps required to upgrade or update or migrate existing Angular 2 apps to Angular 5 apps. Greater details can be found on Angular 5 announcement blog. Upgrade/Update Preparation from Angular 2 to Angular 5 Apps The following are some of the activities which are recommended before the update/upgrade is done: Ensure that extends with lifecycle events are replaced with implements <lifecycle event> In case animation is used in the app, BrowserAnimationsModule from @angular/platform-browser/animations needs to be imported in NgModule OpaqueTokens should be replaced with InjectionTokens Rename the template tags to ng-template tag Update package.json file appropriately to update dependencies and devDependencies Update Package.json file for Dependencies/DevDependencies It is important to update package.json file for upgrading angular apps using Angular 4 …
Oct 2017 – Angular Vs ReactJS – Which one was Popular?
This page represents the popularity of Angular vs ReactJS in October 2017 from different sources including Google Trends etc. It is evident that Angular is seeing greater adoption followed by ReactJS. It is also interesting to note from search keywords trends that Vue.js. Another key observation is the interview questions which developers are seeking in relation with Angular. Google Trends – Angular vs ReactJS Google Popular Search Keywords – Angular vs ReactJS
Angular – Two Ways to Capture User Inputs
This blog represents concepts and code samples which can be used for capturing user inputs from the form in an Angular app using following techniques: Using $event object Using template reference variable Using $event in template statement The following depicts the code which needs to be used in template code. Make a note of The following depicts the code which needs to be used in the component code. Using Template Reference Variables The following depicts the code which needs to be used in template code. Make a note of usage of # (hash) with the template reference variable, email. The reference variable, #email, represents the input element. The following depicts …
Angular Unit Testing Interview Questions – Set 2
This quiz provides basic questions in relation to Angular unit testing. The following are some of the concepts which are covered in this quiz. Angular unit testing fundamentals Angular testing utilities – TestBed [wp_quiz id=”5464″]
Angular Bootstrap Responsive Template – Code Sample
Following code can be placed in the index.html file to adopt Bootstrap 4.* with Angular App (Angular 2 or Angular 4) after you have created an Angular app using Angular CLI commands such as “ng new projectName” which is used for creating a new Angular project. Pay attention to some of the following: Responsiveness is achieved using following code: Bootstrap CSS library is included within head tag. Bootstrap Javascript (optional) is included as part of Body tag In case you are developing web apps using Spring and Angular, check out my book, Building web apps with Spring 5 and Angular. Grab your ebook today and get started.
Angular – How to Handle Password Confirmation Logic
This blog represents code samples and related concepts on how to handle password confirmation logic in an Angular app (Angular 2/Angular 4). Note that the code samples make use of template-driven forms and uses [(ngModel)] for two-way data bindings. Following are key aspects discussed in this blog: Template code for handling password confirmation logic Component code for handling password confirmation logic Signup model code In this blog, it is considered that password confirmation logic is a key part of signup form. Thus, a model name Signup is used. However, the logic can also be used in update password form. Following screenshot represents password confirmation UI related with the code given …
How to Upgrade Angular 4 to Angular 5 Apps
This blog represents steps required to upgrade or update or migrate existing Angular 4 apps to Angular 5 apps. Greater details can be found on Angular 5 announcement blog. I must tell you that upgrading from angular 4 to angular 5 is not like the one represented below (from AngularJS to Angular 2.* and later versions). In this post, you will learn about some of the following: Preparation for upgrading from Angular 4 to Angular 5 Running the upgrade activity Post-upgrade activities Testing the Angular 5 App Upgrade/Update Preparation from Angular 4 to Angular 5 Apps The following are some of the activities which are recommended before the update/upgrade is done: Rename …
Angular Unit Testing Interview Questions – Set 1
This quiz provides basic questions in relation to Angular unit testing. The following are some of the concepts which are covered in this quiz. Angular unit testing fundamentals Angular unit testing tools (Karma & Protractor) Angular testing utilities – TestBed [wp_quiz id=”5463″]
Angular – How to Get Started with Unit Test
This blog represents code sample on how to get started with unit test in an Angular app (Angular 2/Angular 4). The code sample shown below could be used as a template for creating a unit test spec for any component. Unit Test Code Sample for Angular Component Pay attention to following two points: Need to declare component which needs to be tested; In the code shown below, it is the SignupComponent which is tested. Note that SignupComponent represents template-driven form for Signup. In another example, the unit test for AppComponent is shown. Need to declare the modules which are required for testing the component; In the unit test code given …
How to Get User Inputs in Angular – Code Samples
This blog represents tips/techniques and code samples on how to get user inputs in Angular template-driven forms in an Angular app (angular 2/angular 4). Following represents techniques when using template reference variable such as #fieldName with input element. (keyup)=”methodName(fieldName.value)” (keyup.enter)=”methodName(fieldName.value)” (blur)=”methodName(fieldName.value)” Technique 1: (keyup) = “methodName(fieldName.value)” Event keyup helps capture user inputs after every keyup event. The following is the template code: The following is the component code: Technique 2: (keyup.enter) = “methodName(fieldName.value)” Event keyup.enter helps capture user inputs after enter/return button is pressed. The following is the template code: The following is the component code: Technique 3: (blur) = “methodName(fieldName.value)” Event blur helps capture user inputs when user entered some …
Interview Questions – Angular User Input Form Handling
This page represents interview questions in relation to the usage of basic primitives which can be used for handling user input and gestures while working with Angular forms. It covers some of the following topics: Usage of $event object for capturing user inputs Usage of template reference variable for handling user inputs Best practices in relation with using $event object or template reference variables Syntaxes in relation with both $event object and template reference variables [wp_quiz id=”5394″] In case you are developing web apps using Spring and Angular, check out my book, Building web apps with Spring 5 and Angular. Grab your ebook today and get started.
Blockchain – Top 6 Bitcoin Blockchain Explorer
The following are some of the Bitcoin blockchain explorer web applications which can be used to search the transactions, addresses, and blocks and determine the relationships between them. Blockchain Info Bitcoin Block Explorer Insight Bitpay BlockCypher Blocktrail BTC NeoTrackerd Pay attention to some of the following: Height: Height of the block (491105); It implies that 491104 blocks have already been added. Age: Block got created 5 minutes back Transactions: Number of transactions included in the block Size: Size of the block Relayed By:
Sample Bitcoin Block of Bitcoin Blockchain
This blog represents a sample bitcoin block of a Bitcoin Blockchain. Read greater details from this Oreilly book, Mastering Bitcoin. Pay attention to some of the following: Block file format: The block is represented as a file in JSON format Merkle root: Merkle root represents the hash of the root of merkle tree created as a result of combining hash of children nodes. Leaf of the merkle tree represents the hash of the transaction. It takes up 32 bytes of storage. It forms part of Block header. Time: Timestamp when the block is created. It takes up 4 bytes of storage. Forms part of block header. Difficulty: Represents difficult target and takes …
Blockchain Developers Interview Questions – Set 2
This page provides quiz (interview questions) for Blockchain Developers. These are questions, primarily, related with Bitcoin Blockchain. Some of the topics covered are following: Merkle tree Block Mining [wp_quiz id=”5366″]
Spark – How does Apache Spark Work?
This blog represents concepts on how does apache spark work with the help of diagrams. Following are some of the key aspects in relation with Apache Spark which is described in this blog: Apache Spark – basic concepts Apache Spark with YARN & HDFS/HBase Apache Spark with Mesos & HDFS/HBase Apache Spark – Basic Concepts The following represents basic concepts in relation with Spark: Apache Spark with YARN & HBase/HDFS Following are some of the key architectural building blocks representing how does Apache Spark work with YARN and HDFS/HBase. Spark driver program runs on client node. YARN is used as cluster manager. As part of YARN setup, there would be multiple nodes running …
I found it very helpful. However the differences are not too understandable for me