javascript - 在javascript中查找字符串中指定单词的所有索引

Question

如何在冗长的字符串中查找指定单词的所有索引？

let word = 'Testing JavaScript, JavaScript is the Best, JavaScript is Ultimate';

在 JavaScript 代码中从上面的字符串中找到单词“JavaScript”的索引？实际上，这是我的面试问题。

Answer 1

您可以使用以下代码。

let str = 'Testing JavaScript, JavaScript is the Best, JavaScript is Ultimate';
function findAllIndexes(string,word){
  let result = [];
  let dif = 0;
  while(true){
    let index = string.indexOf(word);
    if(index === -1) break;
    else{
      result.push(index + dif);
      let cur = string.length;
      string = string.substring(index + word.length);
      dif += cur - string.length;
    }
  }
  return result;
}
console.log(findAllIndexes(str,"JavaScript"));

Answer 2

您可以使用正则表达式来做到这一点。

let word = 'Testing JavaScript, JavaScript is the Best, JavaScript is Ultimate';
var regex = /JavaScript/gi,result,indices=[];
while((result=regex.exec(word)))
{
  indices.push(result.index);
}
console.log(indices);