Outline
- JavaScript Fundamentals -- What is JavaScript?
- JavaScript Fundamentals -- Variables and Scope
- JavaScript Fundamentals -- Primitive Types
- JavaScript Fundamentals -- The this Keyword
-
JavaScript Fundamentals -- The JavaScript Console
- Introduction
- console.log + Exercise
- console.log Exercise Review
- console.info + Exercise
- console.info Exercise Review
- console.warn + Exercise
- console.warn Exercise Review
- console.error + Exercise
- console.error Exercise Review
- console.table + Exercise
- console.table Exercise Review
- console.assert + Exercise
- console.assert Exercise Review
- console.group + Exercise
- console.group Exercise Review
- Conclusion
-
JavaScript Fundamentals -- Logical and Comparison Operators
- Introduction to Logical and Comparison Operators
- Truthy and Falsy Values
- Comparison Operators -- Equality and Inequality
- Comparison Operators -- Equality and Inequality Exercise
- Comparison Operators -- Equality and Inequality Exercise Review
- Comparison Operators -- Relational
- Comparison Operators -- Relational Exercise
- Comparison Operators -- Relational Exercise Review
- Logical Operators -- Or
- Logical Operators -- Or Exercise
- Logical Operators -- Or Exercise Review
- Logical Operators -- And
- Logical Operators -- And Exercise
- Logical Operators -- And Exercise Review
- Logical Operators -- Not
- Logical Operators -- Not Exercise
- Logical Operators -- Not Exercise Review
- Logical Operators -- Nullish Coalescing
- Logical Operators -- Nullish Coalescing Exercise
- Logical Operators -- Nullish Coalescing Exercise Review
- Logical and Comparison Operators Conclusion
-
JavaScript Fundamentals -- Looping in JavaScript
- Introduction to Looping in JavaScript
- for Loops
- for Loops -- Why Use Them and Gotchas
- for ... of Loops
- Looping Exercise 1
- Looping Exercise 1 Review
- for ... in Loops
- Looping Exercise 2
- Looping Exercise 2 Review
- do while Loops
- Breaking out of Loops
- Skipping Passes Through Loops
- Looping Exercise 3
- Looping Exercise 3 Review
- Conclusion to Looping in JavaScript
-
JavaScript Fundamentals -- Functions in JavaScript
- Introduction to Functions in JavaScript
- Named Functions
- Anonymous Functions
- Arrow Functions
- Functions in JavaScript Exercise 1
- Functions in JavaScript Exercise 1 Review
- Default Parameters
- Named Parameters
- Rest Parameters
- Functions in JavaScript Exercise 2
- Functions in JavaScript Exercise 2 Review
- Functions in JavaScript Real Demo
- Conclusion to Functions in JavaScript
- JavaScript Fundamentals -- Strings, Numbers, & Dates
- JavaScript Fundamentals -- Objects in JavaScript
- JavaScript Fundamentals -- Arrays in JavaScript
- JavaScript Fundamentals -- Course Conclusion
Outline
- JavaScript Fundamentals -- What is JavaScript?
- JavaScript Fundamentals -- Variables and Scope
- JavaScript Fundamentals -- Primitive Types
- JavaScript Fundamentals -- The this Keyword
-
JavaScript Fundamentals -- The JavaScript Console
- Introduction
- console.log + Exercise
- console.log Exercise Review
- console.info + Exercise
- console.info Exercise Review
- console.warn + Exercise
- console.warn Exercise Review
- console.error + Exercise
- console.error Exercise Review
- console.table + Exercise
- console.table Exercise Review
- console.assert + Exercise
- console.assert Exercise Review
- console.group + Exercise
- console.group Exercise Review
- Conclusion
-
JavaScript Fundamentals -- Logical and Comparison Operators
- Introduction to Logical and Comparison Operators
- Truthy and Falsy Values
- Comparison Operators -- Equality and Inequality
- Comparison Operators -- Equality and Inequality Exercise
- Comparison Operators -- Equality and Inequality Exercise Review
- Comparison Operators -- Relational
- Comparison Operators -- Relational Exercise
- Comparison Operators -- Relational Exercise Review
- Logical Operators -- Or
- Logical Operators -- Or Exercise
- Logical Operators -- Or Exercise Review
- Logical Operators -- And
- Logical Operators -- And Exercise
- Logical Operators -- And Exercise Review
- Logical Operators -- Not
- Logical Operators -- Not Exercise
- Logical Operators -- Not Exercise Review
- Logical Operators -- Nullish Coalescing
- Logical Operators -- Nullish Coalescing Exercise
- Logical Operators -- Nullish Coalescing Exercise Review
- Logical and Comparison Operators Conclusion
-
JavaScript Fundamentals -- Looping in JavaScript
- Introduction to Looping in JavaScript
- for Loops
- for Loops -- Why Use Them and Gotchas
- for ... of Loops
- Looping Exercise 1
- Looping Exercise 1 Review
- for ... in Loops
- Looping Exercise 2
- Looping Exercise 2 Review
- do while Loops
- Breaking out of Loops
- Skipping Passes Through Loops
- Looping Exercise 3
- Looping Exercise 3 Review
- Conclusion to Looping in JavaScript
-
JavaScript Fundamentals -- Functions in JavaScript
- Introduction to Functions in JavaScript
- Named Functions
- Anonymous Functions
- Arrow Functions
- Functions in JavaScript Exercise 1
- Functions in JavaScript Exercise 1 Review
- Default Parameters
- Named Parameters
- Rest Parameters
- Functions in JavaScript Exercise 2
- Functions in JavaScript Exercise 2 Review
- Functions in JavaScript Real Demo
- Conclusion to Functions in JavaScript
- JavaScript Fundamentals -- Strings, Numbers, & Dates
- JavaScript Fundamentals -- Objects in JavaScript
- JavaScript Fundamentals -- Arrays in JavaScript
- JavaScript Fundamentals -- Course Conclusion
The find
and findIndex
methods on arrays are very similar. They both allow you to look through an array to find the first item that matches a given condition. find
returns the whole item to you, where findIndex
returns the index where the item is located in the array. If multiple items match the condition, it just returns the first item it finds. If you want all the items that match the condition, use the filter
method that we talked about before. Here's how to use the find
and findIndex
methods:
const names = ['Preston', 'Amanda', 'Joe', 'Brooke' ];
const name = names.find(name => name.includes('a'));
console.log(name); // Amanda
const nameIndex = names.find(name => name.includes('a'));
console.log(nameIndex); // 1
If your condition doesn't match any items in the array, find
will return undefined
and findIndex
will return -1.