Motivation behind this
Today (27th of August, 2020), I have successfully passed JavaScript Developer I Certification. I have been working on JavaScript from a long time along with Lightning Web Components and it has evolved a lot from last few years with ECMA script.
As Salesforce has come up with this exclusive certification with JavaScript language which drives me to learn and earn this which eventually will help me on LWC and other open source development.
This certification is on high demand now-a-days which motivates me to pass and share my tips.
I have given myself around 3 weeks of study time and happy to see me passed. By the way, this exam is tricky and actually challenges the depth of JavaScript knowledge.
Let's get started!
Exam Outline
This certification is comprised of two parts as below:
- Content: 60 multiple-choice/multiple-select questions and 5 non-scored questions
- Time allotted to complete the exam: 105 minutes
- Passing score: 65% (approx 39 questions to be corrected)
- Registration fee: 200 USD
- Delivery options: Online proctored or onsite proctored delivery.
- Prerequisite: None
There were no questions from Lightning Web Components at MCQ.
Lightning Web Components Specialist Superbadge
Link: LWC Specialist
Exclusive Trailmix and Trail:
Preparation
According to my personal choice, I have first targeted to pass MCQ exam and then worked on LWC superbadge.
I have attended Certification Preparation for Salesforce JavaScript Developer I (CRT-600) and finally gone through practice questions following explanations to solve those which immensely helped to pass this exam.
Valuable resources to be referred
My 6 pager cheat sheet: Salesforce JavaScript Developer I Certification Cheat Sheet - 6 Pager
Following blog posts are really helpful to prepare for this exam:
- Passing the Salesforce JavaScript Developer 1 Certification - by Bob Buzzard
- How to Pass the Salesforce JavaScript Developer I Certification Exam - by Bob Lopez
- Tips for passing Salesforce JavaScript Developer Certification - By Avijit Chakraborty
- Prepare for your Salesforce JavaScript developer exam - By Amit Singh
Practice questions : A long list of (advanced) JavaScript questions, and their explanations - by Lydia Hallie
Topics to Consider for Exam
Most of the questions are lengthy code executions and output oriented. Here are following points to be consider along with the syllabus.
Variables, types and Collections
- Different types of Primitive datatypes, Primitive Wrapper, Object variables
- Truthy and falsey evaluations. For example 0, NaN, undefined are falsey
- Difference between == and === operators
- Scenarios of using var, let and const
- Different ways of declaring objects
- JSON transformations
- Collections (Array, Map, Set) and their functions
- String Functions
- Different ways of creating arrays
- Array methods, refer Array
Refer: Grammar & Types,
Objects, Functions and Classes
- Function declarations, calling functions, handling recursions
- Arrow functions
- Create an instance of using Class, Function
- Inheritance and use of super keyword
- Use of Prototype, Refer Object,Prototype
- Use of this
- Spread Syntax
- High order functions like Sort, Map, Filter, Reduce
Browser and Events
- Accessing DOM elements
- Use of getElementById, querySelector, querySelectorAll. Refer querySelector
- Event propagation and effectively stopping that
- Raising CustomEvent
Debugging and Error Handling
- Console Methods like log, error, info
- Using try, catch, finally block for capturing errors Error Handling
Asynchronous Programming
- Callback functions
- Async functions with Promise
- Order of execution when Await with setTimeout, setInternal along with Promise methods and states are involved
Server side JavaScript
- Importing (named, default) and using Node.js functions Refer Node.js API
- Packaging files, checking dependencies, versioning (Major, Minor, Patch)
Testing
- Whitebox and Blackbox testing
- Effectively using console.assert
Hope it will help you to prepare and pass this exam.
Further Reading
- Salesforce JavaScript Developer I Certification Cheat Sheet - 6 Pager
- Developing Product Catalog on Salesforce Lightning Web Components using TreeView Drag and Drop functionality
- Pagination using Salesforce Lightning Web Components with array slicing
- Capture Signature using HTML Canvas inside Salesforce Lightning Web Components
- Describe Objects and Retrieve Records using Salesforce Lightning Web Components flavored with Dynamic Datatable
- Drag and Drop functionality using Salesforce Lightning Web Components leveraging pub-sub event propagation
- Display Google Map using Salesforce Lightning Web Components leveraging modern JavaScript
- Display Combobox values by Lightning Web Components and propagating events to Parent Aura Components
- Salesforce Lightning Web Components Cheat Sheet