如果否则，相同输出（JS）的更多变量[重复]

Question

我正在尝试为同一输出“数学书”添加多个值。我想我缺少一些关于如何格式化括号中的值的基本知识。

<script type="text/javascript">
  <!--
  var book = "maths";
  if (book == "history") {
    document.write("<b>History Book</b>");

    /*How to add more options below besides "maths" so the output will be "Maths
    Book". I want the output to be "Maths Book" also when user enters 
    mathemathics, mata, maths book...

    Do I need more else if lines or I can put additional values in in brackets*/


  } else if (book == "maths") {
    document.write("<b>Maths Book</b>");
  } else {
    document.write("<b>Unknown Book</b>");
  }
  //-->
</script>
<p>Set the variable to different value and then try...</p>

Answer 1

尝试以下脚本和 JSFiddle：https://jsfiddle.net/19d7g8f0/2/ 会有所帮助

function addBook(book){
   if( book == "history" || book=="archive"){
      document.write("<b>History Book</b>");
   }else if( -1 != ["maths","mathematics","arithmetics"].indexOf(book.toLowerCase()) ){
      document.write("<b>Maths Book</b>");
   }else{
      document.write("<b>Unknown Book</b>");
   }
}

addBook("Maths");
addBook("mathematics");
addBook("Arithmetics");