自定义锚点

本示例展示了如何在预览模式下通过外部锚点来定位到文档标题位置。

示例代码：

<template>
  <div>
    <div
      v-for="anchor in titles"
      :style="{ padding: `10px 0 10px ${anchor.indent * 20}px` }"
      @click="handleAnchorClick(anchor)"
    >
      <a style="cursor: pointer">{{ anchor.title }}</a>
    </div>
    <v-md-preview :text="text" ref="preview" />
  </div>
</template>

<script>
const text = `
# heading 1
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent

## heading 2
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent

### heading 3
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent

## heading 2
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent

### heading 3
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent
contentcontentcontent
`;

export default {
  data() {
    return {
      text,
      titles: [],
    };
  },
  mounted() {
    const anchors = this.$refs.preview.$el.querySelectorAll('h1,h2,h3,h4,h5,h6');
    const titles = Array.from(anchors).filter((title) => !!title.innerText.trim());

    if (!titles.length) {
      this.titles = [];
      return;
    }

    const hTags = Array.from(new Set(titles.map((title) => title.tagName))).sort();

    this.titles = titles.map((el) => ({
      title: el.innerText,
      lineIndex: el.getAttribute('data-v-md-line'),
      indent: hTags.indexOf(el.tagName),
    }));
  },
  methods: {
    handleAnchorClick(anchor) {
      const { preview } = this.$refs;
      const { lineIndex } = anchor;

      const heading = preview.$el.querySelector(`[data-v-md-line="${lineIndex}"]`);

      if (heading) {
        // 注意：如果你使用的是编辑组件的预览模式,则这里的方法名改为 previewScrollToTarget
        preview.scrollToTarget({
          target: heading,
          scrollContainer: window,
          top: 60,
        });
      }
    },
  },
};
</script>