vue一步步实现alert功能

.modal-mask{
 position: fixed;
 top: 0;
 left: 0;
 right: 0;
 bottom: 0;
 background-color: rgba(55,55,55,.6);
 z-index: 100;
 display: flex;
 align-items: center;
 justify-content: center;
}
.modal-confirm{
 width: 400px;
 box-sizing: border-box;
 padding: 30px 40px;
 background-color: #fff;
 border-radius: 6px;
}
@media only screen and (max-width: 640px) {
 .modal-confirm{
  width: 100%;
  margin: 0 20px;
  padding: 10px 20px; 
 }
}

<div class="modal-mask" v-show="show">
    <div class="modal-confirm">
      <h2 class="confirm-header">
        <i class="iconfont icon-questioncircle"></i> {{ title }}
      </h2>
      <div class="confirm-content">
        {{ content }}
      </div>
      <div class="confirm-btns">
        <button class="btn" @click="op(1)">取 消</button>
        <button class="btn btn-primary" @click="op(2)">确 定</button>
      </div>
    </div>
  </div>

new Vue({
  el: '#V-confirm',
  data: {
       show: false,
       onCancel: false,
       onOk: false,
       title: '',
       content: ''
     }
  })

 methods: {
   op(type){
    this.show = false
    if(type == '1'){
     if(this.onCancel) this.onCancel()
    }else{
     if(this.onOk) this.onOk()
    }

    this.onCancel = false
    this.onOk = false
    
    document.body.style.overflow = ''
   },
   alert(setting){
    this.title = setting.title || '标题'
    this.content = setting.content || '内容'
    this.onOk = setting.onOk || false
    this.onCancel = setting.onCancel || false
    this.show = true
    document.body.style.overflow = 'hidden'
   }
  }
 }

 var element = document.createElement('div');
 element.id = 'V-confirm'
 element.innerHTML = template
 document.body.appendChild(element)

.modal-enter, .modal-leave {
 opacity: 0;
}
.modal-transition{
 transition: all .3s ease;
}

.modal-enter .modal-confirm,
.modal-leave .modal-confirm {
 transform: scale(1.1);
}
.modal-transition{
 transition: all .3s ease;
}

var setting = {}
  setting.title = '你确定删除吗?'
  setting.content = '删除不可以恢复...'
  setting.onOk = function(){}
  setting.onCancel = function(){}
  
  
$confirm.alert(setting)