How to implement dirty state in VueJs

You can use the deep option of watch as shown in the manual

var app = new Vue({
el: '#app',
data: 
{
  model:
  {
    a:0, 
    b:'', 
    c:
    {
      c1:null, 
      c2:0, 
      c3:'test'
    }
  },
  dirty: false
},
watch:
{
  model:
  {
    handler(newVal, oldVal)
    {
      this.dirty = true;
    },
    deep: true
  }
}
});

Borrowing from -- > https://stackoverflow.com/a/48579303/4050261

You can bind single onchange event on the parent container and benefit from the fact that change events bubble:

<div class="container" @change="someThingChanged()">
  <input v-model="foo">
  <input v-model="bar">
  ... etc.
</div>