add:add clipboard example

src/views/clipboard/index.vue

 <template>
   <div class="app-container">
+    <el-tabs v-model="activeName">
+      <el-tab-pane label="use clipboard  directly" name="directly">
+        <el-input v-model="inputData" placeholder="请输入内容" style='width:400px;'></el-input>
+        <el-button type="primary" icon="document" @click='handleCopy(inputData,$event)'>copy</el-button>
+      </el-tab-pane>
+      <el-tab-pane label="use clipboard by v-directive" name="v-directive">
+        <el-input v-model="inputData" placeholder="请输入内容" style='width:400px;'></el-input>
+        <el-button type="primary" icon="document" v-clipboard:copy='inputData' v-clipboard:success='clipboardSuccess'>copy</el-button>
+      </el-tab-pane>
+    </el-tabs>
+  </div>
+</template>
+
+<script>
+import clip from '@/utils/clipboard' // use clipboard directly
+import clipboard from '@/directive/clipboard/index.js'  // use clipboard by v-directive
+
+export default {
+  directives: {
+    clipboard
+  },
+  data() {
+    return {
+      activeName: 'directly',
+      inputData: 'https://github.com/PanJiaChen/vue-element-admin'
+    }
+  },
+  methods: {
+    handleCopy(text, event) {
+      clip(text, event)
+    },
+    clipboardSuccess() {
+      this.$message({
+        message: '复制成功',
+        type: 'success',
+        duration: 1500
+      })
+    }
+  }
+}
+</script>
+