editor.undoManager.transact(() => {
    const initialRng = editor.selection.getRng();
    if (initialRng.collapsed) {
      applyWordGrab(editor, initialRng);
    }

    // Even after applying word grab, we could not find a selection. Therefore,
    // just make a wrapper and insert it at the current cursor
    if (editor.selection.getRng().collapsed)  {
      const wrapper = makeAnnotation(editor.getDoc(), data, name, settings.decorate);
      // Put something visible in the marker
      Html.set(wrapper, '\u00A0');
      editor.selection.getRng().insertNode(wrapper.dom());
      editor.selection.select(wrapper.dom());
    } else {
      // The bookmark is responsible for splitting the nodes beforehand at the selection points
      // The "false" here means a zero width cursor is NOT put in the bookmark. It seems to be required
      // to stop an empty paragraph splitting into two paragraphs. Probably a better way exists.
      const bookmark = GetBookmark.getPersistentBookmark(editor.selection, false);
      const rng = editor.selection.getRng();
      annotate(editor, rng, name, settings.decorate, data);
      editor.selection.moveToBookmark(bookmark);
    }
  });

 return NamedChain.direct('editor', Chain.mapper((editor) => GetBookmark.getPersistentBookmark(editor.selection, true)), 'bookmark');

//.........这里部分代码省略.........
      };

      const mergeStyles = function (node) {
        let child, clone;

        child = getChildElementNode(node);

        // If child was found and of the same type as the current node
        if (child && !Bookmarks.isBookmarkNode(child) && MatchFormat.matchName(dom, child, format)) {
          clone = dom.clone(child, false);
          setElementFormat(clone);

          dom.replace(clone, node, true);
          dom.remove(child, 1);
        }

        return clone || node;
      };

      childCount = getChildCount(node);

      // Remove empty nodes but only if there is multiple wrappers and they are not block
      // elements so never remove single <h1></h1> since that would remove the
      // current empty block element where the caret is at
      if ((newWrappers.length > 1 || !dom.isBlock(node)) && childCount === 0) {
        dom.remove(node, 1);
        return;
      }

      if (format.inline || format.wrapper) {
        // Merges the current node with it's children of similar type to reduce the number of elements
        if (!format.exact && childCount === 1) {
          node = mergeStyles(node);
        }

        MergeFormats.mergeWithChildren(ed, formatList, vars, node);
        MergeFormats.mergeWithParents(ed, format, name, vars, node);
        MergeFormats.mergeBackgroundColorAndFontSize(dom, format, vars, node);
        MergeFormats.mergeSubSup(dom, format, vars, node);
        MergeFormats.mergeSiblings(dom, format, vars, node);
      }
    });
  };

  if (dom.getContentEditable(selection.getNode()) === 'false') {
    node = selection.getNode();
    for (let i = 0, l = formatList.length; i < l; i++) {
      if (formatList[i].ceFalseOverride && dom.is(node, formatList[i].selector)) {
        setElementFormat(node, formatList[i]);
        return;
      }
    }

    return;
  }

  if (format) {
    if (node) {
      if (node.nodeType) {
        if (!applyNodeStyle(formatList, node)) {
          rng = dom.createRng();
          rng.setStartBefore(node);
          rng.setEndAfter(node);
          applyRngStyle(dom, ExpandRange.expandRng(ed, rng, formatList), null, true);
        }
      } else {
        applyRngStyle(dom, node, null, true);
      }
    } else {
      if (!isCollapsed || !format.inline || dom.select('td[data-mce-selected],th[data-mce-selected]').length) {
        // Obtain selection node before selection is unselected by applyRngStyle
        const curSelNode = ed.selection.getNode();

        // If the formats have a default block and we can't find a parent block then
        // start wrapping it with a DIV this is for forced_root_blocks: false
        // It's kind of a hack but people should be using the default block type P since all desktop editors work that way
        if (!ed.settings.forced_root_block && formatList[0].defaultBlock && !dom.getParent(curSelNode, dom.isBlock)) {
          applyFormat(ed, formatList[0].defaultBlock);
        }

        // Apply formatting to selection
        ed.selection.setRng(RangeNormalizer.normalize(ed.selection.getRng()));
        bookmark = GetBookmark.getPersistentBookmark(ed.selection, true);
        applyRngStyle(dom, ExpandRange.expandRng(ed, selection.getRng(), formatList), bookmark);

        if (format.styles) {
          MergeFormats.mergeUnderlineAndColor(dom, format, vars, curSelNode);
        }

        selection.moveToBookmark(bookmark);
        FormatUtils.moveStart(dom, selection, selection.getRng());
        ed.nodeChanged();
      } else {
        CaretFormat.applyCaretFormat(ed, name, vars);
      }
    }

    Hooks.postProcess(name, ed);
  }
};

//.........这里部分代码省略.........
          const marker = Option.from(startContainer.firstChild).getOr(startContainer);
          splitToFormatRoot(wrapWithSiblings(dom, marker, true, 'span', { 'id': '_start', 'data-mce-type': 'bookmark' }));
          unwrap(true);
          return;
        }

        // Wrap and split if nested
        if (isChildOfInlineParent(dom, endContainer, startContainer)) {
          const marker = Option.from(endContainer.lastChild).getOr(endContainer);
          splitToFormatRoot(wrapWithSiblings(dom, marker, false, 'span', { 'id': '_end', 'data-mce-type': 'bookmark' }));
          unwrap(false);
          return;
        }

        // Wrap start/end nodes in span element since these might be cloned/moved
        startContainer = wrap(dom, startContainer, 'span', { 'id': '_start', 'data-mce-type': 'bookmark' });
        endContainer = wrap(dom, endContainer, 'span', { 'id': '_end', 'data-mce-type': 'bookmark' });

        // Split start/end
        splitToFormatRoot(startContainer);
        splitToFormatRoot(endContainer);

        // Unwrap start/end to get real elements again
        startContainer = unwrap(true);
        endContainer = unwrap();
      } else {
        startContainer = endContainer = splitToFormatRoot(startContainer);
      }

      // Update range positions since they might have changed after the split operations
      rng.startContainer = startContainer.parentNode ? startContainer.parentNode : startContainer;
      rng.startOffset = dom.nodeIndex(startContainer);
      rng.endContainer = endContainer.parentNode ? endContainer.parentNode : endContainer;
      rng.endOffset = dom.nodeIndex(endContainer) + 1;
    }

    // Remove items between start/end
    RangeWalk.walk(dom, rng, function (nodes) {
      each(nodes, function (node) {
        process(node);

        // Remove parent span if it only contains text-decoration: underline, yet a parent node is also underlined.
        if (NodeType.isElement(node) && ed.dom.getStyle(node, 'text-decoration') === 'underline' &&
          node.parentNode && FormatUtils.getTextDecoration(dom, node.parentNode) === 'underline') {
          removeFormat(ed, {
            deep: false,
            exact: true,
            inline: 'span',
            styles: {
              textDecoration: 'underline'
            }
          }, null, node);
        }
      });
    });
  };

  // Handle node
  if (node) {
    if (node.nodeType) {
      rng = dom.createRng();
      rng.setStartBefore(node);
      rng.setEndAfter(node);
      removeRngStyle(rng);
    } else {
      removeRngStyle(node);
    }

    return;
  }

  if (dom.getContentEditable(selection.getNode()) === 'false') {
    node = selection.getNode();
    for (let i = 0, l = formatList.length; i < l; i++) {
      if (formatList[i].ceFalseOverride) {
        if (removeFormat(ed, formatList[i], vars, node, node)) {
          break;
        }
      }
    }

    return;
  }

  if (!selection.isCollapsed() || !format.inline || dom.select('td[data-mce-selected],th[data-mce-selected]').length) {
    bookmark = GetBookmark.getPersistentBookmark(ed.selection, true);
    removeRngStyle(selection.getRng());
    selection.moveToBookmark(bookmark);

    // Check if start element still has formatting then we are at: "<b>text|</b>text"
    // and need to move the start into the next text node
    if (format.inline && MatchFormat.match(ed, name, vars, selection.getStart())) {
      FormatUtils.moveStart(dom, selection, selection.getRng());
    }

    ed.nodeChanged();
  } else {
    CaretFormat.removeCaretFormat(ed, name, vars, similar);
  }
};