JS 获取选中文本的所有 DOM 块元素

问题

在网页上选中文本，然后获取选中文本的所有 DOM 块元素。

解决

var selection = window.getSelection();
var range = selection.getRangeAt(0);
var allWithinRangeParent = range.commonAncestorContainer.getElementsByTagName("*");

var allSelected = [];
for (var i=0, el; el = allWithinRangeParent[i]; i++) {
  // The second parameter says to include the element 
  // even if it's not fully selected
  if (selection.containsNode(el, true) ) {
    allSelected.push(el);
  }
}

console.log('All selected =', allSelected);

function getSelectedBlockElements() {
  const selection = window.getSelection();
  if (selection.rangeCount === 0) return [];
  const range = selection.getRangeAt(0);
  const startContainer = range.startContainer;
  const endContainer = range.endContainer;
  const startElement = startContainer.nodeType === 3 ? startContainer.parentElement : startContainer;
  const endElement = endContainer.nodeType === 3 ? endContainer.parentElement : endContainer;
  const commonAncestor = range.commonAncestorContainer;
  const commonAncestorElement = commonAncestor.nodeType === 3 ? commonAncestor.parentElement : commonAncestor;
  const startElementParents = [startElement];
  let startElementParent = startElement.parentElement;
  while (startElementParent !== commonAncestorElement) {
    startElementParents.push(startElementParent);
    startElementParent = startElementParent.parentElement;
  }
  const endElementParents = [endElement];
  let endElementParent = endElement.parentElement;
  while (endElementParent !== commonAncestorElement) {
    endElementParents.push(endElementParent);
    endElementParent = endElementParent.parentElement;
  }
  const blockElements = [];
  let startElementParentsIndex = 0;
  let endElementParentsIndex = 0;
  let startElementParentElement = startElementParents[startElementParentsIndex];
  let endElementParentElement = endElementParents[endElementParentsIndex];
  while (startElementParentElement !== endElementParentElement) {
    blockElements.push(startElementParentElement);
    startElementParentsIndex++;
    startElementParentElement = startElementParents[startElementParentsIndex];
  }
  blockElements.push(startElementParentElement);
  return blockElements;
}

后记

• https://stackoverflow.com/questions/4220478/get-all-dom-block-elements-for-selected-texts