JavaScript Stringオブジェクトのメソッドとプロパティ

JavaScript 目次 - ray88’s diary
JavaScript Stringオブジェクト - ray88’s diary
JavaScript 文字列内を検索する・IndexOfメソッドとlastIndexOfメソッド・includesメソッド - ray88’s diary
■Stringオブジェクトのメンバー

function myFunction(){
  let str = "My name is Bob.";

  console.log(str.length);//115
  console.log(str.charAt(0));//M
  console.log(str.charCodeAt(0));77

  console.log(str.toLocaleLowerCase());//my name is bob.
  console.log(str.toLocaleUpperCase());//MY NAME IS BOB.

  console.log(str.slice(3,7));//name
  console.log(str.substr(3,7));//name is

  console.log(str.split(' '));//['MY','name','is','BOb.']
  console.log(str.startsWith('My'));//true
  console.log(str.startsWith('Bob',11));true
  console.log(str.endsWith('Bob.'));//true
  console.log(str.endsWith('My',2));true

  str = str.concat(" My dog's name is also Bob.")
  console.log(str);//My name is Bob.My dog's name is also Bob.

  console.log(str.indexOf('Bob'));//11
  console.log(str.lastIndexOf('Bob'));//38
  console.log(str.includes('Bob'));//true

  console.log('1234'.padStart(7,'0'));//0001234
  console.log('1234'.padEnd(7,'0'));//1234000

  console.log('Bob'.localeCompare('Abc'));//1
  console.log('Bob'.localeCompare('Bob'));//0
  console.log('Bob'.localeCompare('Cde'));//-1
  

  console.log('Bob'.repeat(3));//BobBobBob
  console.log('       Bob       '.trim());//Bob
}

■Lengthプロパティ
　Stringオブジェクトの唯一のプロパティ

文字列.length