diff --git a/nodeJS/Learning/01/index.js b/nodeJS/Learning/01/index.js index 88a53dd..0e48141 100644 --- a/nodeJS/Learning/01/index.js +++ b/nodeJS/Learning/01/index.js @@ -85,4 +85,255 @@ console.log(x); //Null: telling them theres nothing in the code let y = null; -console.log(y); \ No newline at end of file +console.log(y); + +//Non-primitive data type: anything thats not within the box// +//Object, Array, Function// + +//Object: sth to define a list of things, e.g. list of primitive data types// +// const or let -> {curly}, can contain diff. data types + +const user = { + name1: "John", + age: 5, + verified: true, + + //Nested object (within the object) + address: { + city: "New York", + state: "NY", + } +} + +console.log(user) +console.log(user.address.state) + +//Array: a list of primitive data types within one category, only one type of data +const fruits = ["Apple", "Banana", "Cherry", "Dates"]; +const numbers = [1, 2, 3, 4, 5]; + +//Array, has string indexing stuff +console.log(fruits[2]) // Cherry + +//Function +// y = f(x) = 2x + 1 +// y -output, x-input + +function add(x) { + return 2*x + 1; +} + +add (5); +console.log(add(5)); //11 + +//greet is the function name +// ${}: must use `(next to 1) +function greet(name) { + return `Hello, ${name}`; +} +console.log(greet('Tiffany')); // Hello Tiffany + +let functionName = function(x) { + return 2*x + 1; +} + +//best practice to declare a function +const arrowFunction = (x) => { + return 2*x + 1; +} + +//Operators, things we can do with the data types + +//Arithmetic operators +// e.g. + - * / ++ -- + +let a = 10; +let b = 5; + +console.log(a + b); //15 +console.log(a - b); //5 +console.log(a * b); //50 +console.log(a/b); //2 +console.log(a % b) //0 (remainder of division) +console.log(a++); //11 (a = a + 1) +console.log(a--); //9 (a = a-1) + +//Assignment operators +// =, +=, -=, *=, /=, %= + +let c = 10 +let d = 5 + +c += d; //c = c + d + +//Comparison operators, comparing stuffs +// ==, !=, >, <, >=, <=, ===, !== + +let e = "10" +let f = 10 + +console.log(e == f); // false (is e equal to f) + +console.log(e === f) //false, absolutely equal to, which it is not, but if == + +//Logical Operators +//&&(AND), ||(OR), ! (NOT) + +let g = 10; +let h = 5; + +console.log(g > 5 && h > 10); //false +console.log(g > 5 || h > 10); //true +console.log(!(g > 5)); //false, just reverse whats inside + +//Control structures +//If statements + +// if (condition) { +// //result +// } + +let i = 2; + +if (i > 5) { + console.log("I am smart") +} + +//If-Else statement +let j = 10; + +if (j > 5) { + console.log("Ronald believes in Tiffany's religion") +} else { + console.log("Ronald does not believe in Tiffany's religion") +} + +// If Else If statement +let k = 10 + +if (k > 5) { + console.log("k is larger than 5"); +} else if (k < 5) { + console.log("k is less than 5"); +} else if (k === 5) { + console.log("k is equal to 5"); +} else { + console.log("k is not a number"); +} + +//Different way to announce if statement, ternary operator + +let n = 10; +//condition ?(if) expression1(true) : expression 2(false) +n > 5 ? console.log("n is greater than 5") : console.log("n is smaller than 5"); + +// Switch statement +let day = "Monday"; + +switch(day) { + case "Monday": + console.log("Today is Monday \:\(") + break; + case "Tuesday": + console.log("Today is Tuesday") + break; + default: + console.log("No day") + break; +} + +// switch(condition) { +// case value1: +// //code block +// break; (end of this case) +// case value2: +// //code block +// break; +// default: +// //code block +// break; +// } + + + +//Loops, usually a number to loop + +// For Loop +// for (initialization; condition; increment/decrement) { +// //code block +// } + +for (let i = 0; i < 5; i++) { + console.log("Tiffany is smart"); +} + +// While Loop, anything within the condition, if it's still true, will keep running +// while(condition) { +// // code block +// } + +let m = 0; + +while (m<5) { + console.log("Tiffany is smart"); + m++; +} + +// For In Loop, comma within object (for objects) +let person2 = { + name: "Tiffany", + age: 24, + isSmart: true, +} + +//key can be any name, eg color, looping the list +for (let key in person2) { + console.log(key, person2[key]); +} + +// For of Loop (for arrays) +let numbers1 = [1, 2, 3, 4, 5] + +for (let number of numbers1) { + number += 1; // number= number + 1 + console.log(number); +} + +//Do While Loop + +//do { +// // code block +// } while (condition); + +let happy = 0 + +do { + console.log("Tiffany is the savior"); + happy++; +} while (happy < 5) + +//looping "tiffany is the savior" using happy (plus 1 for each round) +// until happy reaches a number larger than 5 + +// Classes: recipe book or instruction +//constructor, like ingredients + +class bread { + constructor(flour, water, salt) { + this.flour = flour; + this.water = water; + this.salt = salt; + } + + bake() { + console.log(`Baking Bread with ${this.flour}, using ${this.water} cups of water and ${this.salt} tsp of salt.`); + } +} +const bread1 = new bread("wheat", 2, 3) + +bread1.bake() + +// Modules: it only happens in a modules + +//Import +//import {greet} from "./greet.js";