Get selected record IDs for custom added admin button

[rifkidocs]

@Daxur

const getCheckedIDs = () => {
    let ids = []
    document.querySelectorAll('input[type="checkbox"]:checked').forEach(c => {
      const elements = c.parentElement.parentElement.querySelectorAll('td[aria-colindex="2"] > span')
      if (elements.length > 0) ids.push(elements[0].textContent)
    })
    console.log("selected ids", ids)
    return ids
  }

how to use this in custom button components? can you show me the full code?