js中字符每次出现的位置

function findAllOccurrences(str, char) {
  let positions = [];
  let pos = str.indexOf(char);

  while (pos !== -1) {
    positions.push(pos);
    pos = str.indexOf(char, pos + 1); // 从当前位置的下一个字符开始搜索
  }

  return positions;
}

// 示例使用
const myString = "hello world, hello universe";
const characterToFind = "o";
const occurrences = findAllOccurrences(myString, characterToFind);

console.log(`字符 "${characterToFind}" 在字符串中出现的所有位置:`, occurrences);

function findAllOccurrencesIgnoreCase(str, char) {
  let positions = [];
  let lowerStr = str.toLowerCase();
  let lowerChar = char.toLowerCase();
  let pos = lowerStr.indexOf(lowerChar);

  while (pos !== -1) {
    positions.push(pos);
    pos = lowerStr.indexOf(lowerChar, pos + 1);
  }

  return positions;
}