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CSS

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JavaScript

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HTML 

              
                h1 為什麼畫面沒有隨資料更新 — 深入 Vue 響應式原理筆記（陣列部分）
hr
p.quotation 此篇文章為整理自 #[a(href="https://cn.vuejs.org/v2/guide/list.html#注意事项") Vue 官網 列表渲染注意事項] 之筆記


#change-by-array-index(v-cloak)
    h3 利用索引值變更 index 0 的值（無法響應式變化）
    input(type="text" v-model="animal")
    button(v-on:click="changeAnimal") Change Animal
    ul
        li(v-for="item in animals" v-bind:key="item") {{ item }}
    button(v-on:click="$forceUpdate()") forceUpdate
    

#change-by-splice(v-cloak)
    h3 方法一：利用 splice 達到響應式變化
    input(type="text" v-model="animal")
    button(v-on:click="changeAnimal") Change Animal
    ul
        li(v-for="item in animals" v-bind:key="item") {{ item }}
    
    
#change-by-set(v-cloak)
    h3 方法二：利用 vm.$set 達到響應式變化
    input(type="text" v-model="animal")
    button(v-on:click="changeAnimal") Change Animal
    ul
        li(v-for="item in animals" v-bind:key="item") {{ item }}
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CSS 

              
                $green: #41CEC0;
$vue: #41b883;
$blue: #35495e;
$purple: #A53860;
$red: #C63647;
$yellow: #FFDF2C;
$orange: #E96900;

[v-cloak]{
  display: none;
}
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JS 

              
                
/**
 * change by array index
 **/
new Vue({
    el: '#change-by-array-index',
    data: {
        animal: "",
        animals: ['<YOURAnimal>', 'cat', 'penguin', 'bird', 'rabbit']
    },
    methods: {
        changeAnimal(){
            // 當利用陣列索引直接設置值時
            this.animals[0] = this.animal
        }
    }
})

/**
 * change by splice
 **/
new Vue({
    el: '#change-by-splice',
    data: {
        animal: "",
        animals: ['<YOURAnimal>', 'cat', 'penguin', 'bird', 'rabbit']
    },
    methods: {
        changeAnimal(){
            // 利用 arr.splice(startIndex, deleteCount, addItem)
            this.animals.splice(0, 1, this.animal)
        }
    }
})


/**
 * change by set
 **/
new Vue({
    el: '#change-by-set',
    data: {
        animal: "",
        animals: ['<YOURAnimal>', 'cat', 'penguin', 'bird', 'rabbit']
    },
    methods: {
        changeAnimal(){
            // 利用 vm.$set(array, index, value) 方法
            this.$set(this.animals, 0, this.animal)
        }
    }
})
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999px

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