JavaScript 스타일 가이드 - Strings

원문:https://github.com/airbnb/javascript

• 문자열은 작은 따옴표''를 사용하자.
  

  // bad
  var name = "Bob Parr";
  
  // good
  var name = 'Bob Parr';
  
  // bad
  var fullName = "Bob " + this.lastName;
  
  // good
  var fullName = 'Bob ' + this.lastName;
  

• 80 문자 이상의 문자열은 문자열 연결을 사용하여 여러 줄에 걸쳐 기술 할 필요가 있다.
• Note : 문자열 연결을 많이하면 성능에 영향을 줄 수 있다.

  // bad
  var errorMessage = 'This is a super long error that was thrown because of Batman. When you stop to think about how Batman had anything to do with this, you would get nowhere fast.';
  
  // bad
  var errorMessage = 'This is a super long error that \
  was thrown because of Batman. \
  When you stop to think about \
  how Batman had anything to do \
  with this, you would get nowhere \
  fast.';
  
  // good
  var errorMessage = 'This is a super long error that ' +
    'was thrown because of Batman.' +
    'When you stop to think about ' +
    'how Batman had anything to do ' +
    'with this, you would get nowhere ' +
    'fast.';
  

• 프로그램에서 문자열을 생성 할 필요가 있는 경우 (특히 IE는) 문자열 연결 대신 Array#join을 사용하자.

  var items,
      messages,
      length,
      i;
  
  messages = [{
      state: 'success',
      message: 'This one worked.'
  },{
      state: 'success',
      message: 'This one worked as well.'
  },{
      state: 'error',
      message: 'This one did not work.'
  }];
  
  length = messages.length;
  
  // bad
  function inbox(messages) {
    items = '<ul>';
  
    for (i = 0; i < length; i++) {
      items += '<li>' + messages[i].message + '</li>';
    }
  
    return items + '</ul>';
  }
  
  // good
  function inbox(messages) {
    items = [];
  
    for (i = 0; i < length; i++) {
      items[i] = messages[i].message;
    }
  
    return '<ul><li>' + items.join('</li><li>') + '</li></ul>';
  }