Copy string to clipboard.

copyStringToClipboard.ts

/**
 * Copy a string to the clipboard.
 * @param string 
 */
export function copyToClipboard(string: string): boolean {
  let textarea: HTMLTextAreaElement
  let result: boolean

  try {
    navigator.clipboard.writeText(string)
  } catch (e) {
    try {
      textarea = document.createElement('textarea')
      textarea.setAttribute('position', 'fixed')
      textarea.setAttribute('top', '0')
      textarea.setAttribute('readonly', 'true')
      textarea.setAttribute('contenteditable', 'true')
      textarea.style.position = 'fixed' // prevent scroll from jumping to the bottom when focus is set.
      textarea.value = string

      document.body.appendChild(textarea)

      textarea.focus()
      textarea.select()

      const range = document.createRange()
      range.selectNodeContents(textarea)

      const sel = window.getSelection()
      sel.removeAllRanges()
      sel.addRange(range)

      textarea.setSelectionRange(0, textarea.value.length)
      result = document.execCommand('copy')
    } catch (err) {
      result = null
    } finally {
      document.body.removeChild(textarea)
    }
  }

  return !!result
}