Update data using vuex

问题

As Vuex, I'm trying to update an object using form. My code like this.

In store:

const state = {
   categories: []
};

//mutations:
[mutationType.UPDATE_CATEGORY] (state, id, category) {
    const record = state.categories.find(element => element.id === id);
    state.categories[record] = category;
}

//actions:
updateCategory({commit}, id, category) {
  categoriesApi.updateCategory(id, category).then((response) => {
    commit(mutationType.UPDATE_CATEGORY, id, response);
    router.push({name: 'categories'});
  })
}

Template in .Vue file:

    <form>
      <div class="form-group">
        <label for="Name">Name</label>
        <input
          type="text"
          class="form-control form-control-sm"
          name="name"
          v-model.lazy="category.name" required>
      </div>

      <div class="form-group">
        <label for="Slug">Slug</label>
        <input
          type="text"
          class="form-control form-control-sm"
          name="slug"
          v-model.lazy="category.slug" required>
      </div>

      <div class="form-group">
        <label for="Avatar">Avatar</label>
        <input
          type="text"
          class="form-control form-control-sm"
          name="avatar"
          v-model.lazy="category.avatar" required>
      </div>

      <div class="form-group">
        <label for="Description">Description</label>
        <textarea
          type="text"
          class="form-control form-control-sm"
          rows="5"
          name="description"
          v-model.lazy="category.description"></textarea>
      </div>

      <div class="form-group">
        <button type="submit" @click.prevent="updateCategory" class="btn btn-outline btn-sm">Update</button>
      </div>

    </form>

And in script:

export default {
    data() {
      return {
        category: {}
      }
    },

    methods: {
      getCategoryById(id) {
        axios.get(`categories/${id}`)
          .then(response => {
            this.category = response.data;
          })
          .catch(error => {
            console.log(error);
          })
      },

      // Using mutation.
      updateCategory() {
        this.$store.dispatch('updateCategory', this.$route.params.id, this.category);
        console.log(this.category); //Display exactly data changed.
      }
    },

    created() {
      this.getCategoryById(this.$route.params.id);
    }
}

My problem is when I click Update. It nothing change. I did print category Object in console. It displays exactly what I expected. But after click Update button. It hasn't changed.

Anyone can tell me why and give me solution?? Thanks.

回答1:

You can wrap your parameters in 1 payload object:

In your component

this.$store.dispatch('updateCategory', {
  id: this.$route.params.id,
  data: this.category
});

in your store, you need to made new object when edit categories array (you can read more about immutable)

const state = {
   categories: []
};

//mutations:
[mutationType.UPDATE_CATEGORY] (state, payload) {
    state.categories = state.categories.map(category => {
      if (category.id === payload.id) {
        return Object.assign({}, category, payload.data)
      }
      return category
    })
}

//actions:
updateCategory({commit}, payload) {
  categoriesApi.updateCategory(payload.id, payload.data).then((response) => {
    commit(mutationType.UPDATE_CATEGORY, payload);
    router.push({name: 'categories'});
  })
}

回答2:

ES6 way of updating

//mutations UPDATE:
[mutationType.UPDATE_CATEGORY] (state, payload) {
    state.categories = [
        ...state.categories.map(item => 
            item.id !== updatedItem.id ? item : {...item, ...updatedItem}
        )
    ]
}

//mutations CREATE:
[mutationType.CREATE_CATEGORY] (state, category) {
    state.categories = [category, ...state.categories] //Append to start of array
}

//mutations DELETE:
[mutationType.DELETE_CATEGORY] (state, id) {
    state.categories = [
       ...state.categories.filter((item) => item.id !== id)
    ];
}

回答3:

and much more simple, just use methods to modify arrays (never modify them directly) (check this: https://vuejs.org/2016/02/06/common-gotchas/#Why-isn%E2%80%99t-the-DOM-updating even old and DOM related, is still valid)

So just find your object and replace with splice in your mutation:

const index = state.objectsArray.map(o => o.id).indexOf(newObject.id);
state.objectsArray.splice(index, 1, newObject);

来源：https://stackoverflow.com/questions/50416063/update-data-using-vuex