Javascript – Working with strings

String methods

string.indexOf('') // gives position of needle in haystack
string.lastIndexOf('') // if there are multiple

sting.slice(i, ii) // remove the first i and last ii characters of string

string.slice(-i) // Save last i of string

string.slice(0, string.indexOf(' ')) // gets first word.

string.toLowerCase();
string.toUpperCase();
string.trim(); removes LEADING spaces and \n

const normalizedEmail = eMail.toLowerCase().trim();

// replacing
.replace(item, replacement) // replace first appearance
.replaceAll() // replaces all // ***New method***

.replace(/string/g, replacement) // replacing with global exoressions

// Booleans
string.includes()
string.startsWith()
string.endsWith()


//Split and join
console.log('a+lovely+string'.split(+)) // returns an array
const [firstName, lastName] = "Duncan Samwell".split(' ') // creates an array
const newName = ['Mr.' firstName, lastName].join();

//Capitalize function
const capitalizeName = function(name) {
 const names = name.split(' ');
 for (const n of names) {
  n[0].toUpperClass() + n.slice(1);
  n.push(n.replace(n[0], n[0].toUpperCase());
 }
}

//Padding
string.padStart(n, p) // fill string with p until entire string is length of n
string.padEnd(n, p)

// Example for Credit Card
const maskCreditCard = function(cc) {
 const l = cc.length;
 const lastFour = cc.slice(-4);
 return lastFour.padStart(l, '*');
}


//repeat
string.repeat(x) // repeat x amount of times

String Methods Practice

/*
///////////////////////////////////////
// String Methods Practice
*/

const flights =
  '_Delayed_Departure;fao93766109;txl2133758440;11:25+_Arrival;bru0943384722;fao93766109;11:45+_Delayed_Arrival;hel7439299980;fao93766109;12:05+_Departure;fao93766109;lis2323639855;12:30';

// 🔴 Delayed Departure from FAO to TXL (11h25)
//              Arrival from BRU to FAO (11h45)
//   🔴 Delayed Arrival from HEL to FAO (12h05)
//            Departure from FAO to LIS (12h30)

const getCode = flights.split('+');

const l = getCode[0].length;

for (const line of getCode) {
  const section = line.split(';');
  // Status
  let status = section[0].slice(1).replace('_', ' ');
  if (status.startsWith('Delayed')) status = '🔴 ' + status;
  // From
  let from = section[1][0] + section[1][1] + section[1][2];
  // To
  let to = section[2][0] + section[2][1] + section[2][2];
  // Clock
  let clock = section[3].replace(':', 'h');

  const output = status + ' from ' + from.toUpperCase() + ' to ' + to.toUpperCase() + ' (' + clock + ')';

  console.log(output.padStart(l - 6));
}

Alternative

const flights =
  '_Delayed_Departure;fao93766109;txl2133758440;11:25+_Arrival;bru0943384722;fao93766109;11:45+_Delayed_Arrival;hel7439299980;fao93766109;12:05+_Departure;fao93766109;lis2323639855;12:30';

// 🔴 Delayed Departure from FAO to TXL (11h25)
//              Arrival from BRU to FAO (11h45)
//   🔴 Delayed Arrival from HEL to FAO (12h05)
//            Departure from FAO to LIS (12h30)

const getCode = str => str.slice(0, 3).toUpperCase();

for (const flight of flights.split('+')) {
  const [type, from, to, time] = flight.split(';');
  const output = `${type.startsWith('_Delayed') ? '🔴' : ''}${type.replaceAll(
    '_',
    ' '
  )} ${getCode(from)} ${getCode(to)} (${time.replace(':', 'h')})`.padStart(36);
  console.log(output);
}