<div>
   <el-button type="primary" @click="onShow">点我</el-button>
</div>

<addForm :show="formShow" @onHide="formShow = false"></addForm>

import addForm from './docsForm'
export default {
components: {
addForm
},
data() {
return {
show: false,
formShow: false
}
},
watch: {
 show: {
      handler: function(newVal, oldVal) {
        this.show = newVal
      },
      deep: true
    }
},
methods: {
onShow() {
      this.formShow = true
    }
}
}

<slidePanel :width="550" :show="show" title="添加知识" @changeShow="hide">
<div class="docs-body">
</div>
</slidePanel>
export default {
props: {
show: false
},
methods: {
hide() {
      this.$emit('onHide')
    },
}

<template>
  <transition name="slide-panel-fade">
    <div v-if="show" class="slide-panel" :style="{ width: width + 'px'}">
      <div class="slide-panel-layout">
        <div class="slide-panel-header">
          <h3 class="slide-panel-header-title">{{title}}</h3>
          <button class="slide-panel-header-close" @click="onShow"><i class="el-icon-close"></i></button>
        </div>
        <div class="slide-panel-body">
          <slot></slot>
        </div>
      </div>
    </div>
  </transition>
</template>
<script>
export default {
  props: {
    title: String,
    show: Boolean,
    width: {
      type: Number,
      default: 500
    }
  },
  methods: {
    onShow() {
      this.$emit('changeShow', false)
    }
  },
  watch: {
    show: {
      handler: function(newVal, oldVal) {
        this.show = newVal
      },
      deep: true
    }
  },
  mounted() {
    document.body.appendChild(this.$el)
  },
  destroyed() {
    this.$el.remove()
  }
}
</script>