完成作业

src/components/HelloWorld.vue

@@ -1,5 +1,5 @@
 <template>
-  <div class="hello" data-spma="aa">
+  <div class="hello" data-spma="aa" @click="clickDivSpam">
     <span>show spm:{{spmText}}</span>
     <div data-spmb="bb">
       <button data-spmc="cc">Click it</button>
@@ -16,9 +16,41 @@ export default {
   name: 'HelloWorld',
   data: ()=>{
     return {
-      spmText: 'xx.xx.xx'
+      spmText: 'xx.xx.xx',
     }
-  }
+  },
+  /** 事件监听无法跑通用例
+  mounted() {
+    const helloNode = document.querySelector('.hello');
+    if (!helloNode) return;
+    helloNode.addEventListener('click', (e) => {
+      const arr = this.findMark(e.target);
+      this.spmText = arr.reverse().join('.')
+    })
+  },
+  beforeUnmount() {
+  },
+   */
+  methods: {
+    clickDivSpam(e) {
+      const arr = this.findMark(e.target);
+      this.spmText = arr.reverse().join('.')
+    },
+    findMark(target, res = []) {
+      const attributes = target.dataset;
+      if (!attributes) return res;
+      for(let k in attributes) {
+        if(k.startsWith('spm')) {
+          res.push(attributes[k]);
+        }
+      }
+
+      if (target.parentNode) {
+        this.findMark(target.parentNode, res);
+      }
+      return res;
+    },
+  },
 }
 </script>