Question

我正在试图找出如何返回一个句子，我有一个项目列表，我必须用“，”分隔它们。但是，如果数组只包含一个项目，则只返回没有逗号的单词，如果有两个单词，则在第一个单词之后返回一个逗号，而不是最后一个。

var conceptList = ['apple', 'orange', 'banana'];
var concepts = joinList(conceptList);

function joinList() {

  for (var i = 0; i < conceptList.length; i++) {
    if (conceptList.length) {
      conceptList[i];
    }  
  return conceptList;
  }
}

console.log("Today I learned about " + concepts + ".");

Answer 1

这样做的简单方法是将每个元素附加到字符串，然后是', '，然后在返回字符串之前删除尾随', '。

＆＃13;

/*
* Write a loop that joins the contents of conceptList together
* into one String, concepts, with each list item separated from
* the previous by a comma.
*
* Note: you may not use the built-in Array join function.
*/

var conceptList = ['apple', 'orange', 'banana'];
// a custom function written by you (you must define it too!)
var concepts = joinList(conceptList);

function joinList() {
  var str = '';
  for (var i = 0; i < conceptList.length; i++) {
    str += conceptList[i] + ', ';
  }
  
  return str.substr(0, str.length-2);
}

console.log("Today I learned about " + concepts + ".");

＆＃13;

在没有.join（）的数组中加入项目列表

1 个答案: