如何在没有javascript方法的字符串中搜索给定的字符串？

function searchInString(str, target) {
  let index = 0;
  let result = [];

  while (index !== -1) {
    index = str.indexOf(target, index);
    if (index !== -1) {
      result.push(index);
      index += target.length;
    }
  }

  return result;
}

const originalString = "This is a sample string. Sample is a keyword.";
const searchString = "sample";

const occurrences = searchInString(originalString, searchString);
console.log(occurrences); // Output: [10, 27]

function searchInString(str, target) {
  const regex = new RegExp(target, "g");
  let result = [];
  let match;

  while ((match = regex.exec(str)) !== null) {
    result.push(match.index);
  }

  return result;
}

const originalString = "This is a sample string. Sample is a keyword.";
const searchString = "sample";

const occurrences = searchInString(originalString, searchString);
console.log(occurrences); // Output: [10, 27]