因为过滤比Vue 1复杂得多,所以我有一个问题。
这是我的组件,其中显示了绵羊列表,其中包含搜索/过滤名称或族的选项。 但我无法弄清楚如何实现这一目标。
<input type="search" v-model="search" placeholder="Search for Name OR Family" />
<ul>
<li v-for="sheep in sheeps"> <!-- Tried also: 'sheep in filteredSheeps' -->
{{ sheep.name }} ({{ sheep.type }}/{{ sheep.family }} )
</li>
</ul>
<script>
import axios from 'axios';
export default {
data() {
return {
sheeps: [],
search: '',
};
},
mounted() {
this.getSheeps();
}
methods: {
getSheeps() {
var self = this;
const url = '/api/sheeps';
axios.get(url).then(function(response) {
self.sheeps = response.data;
});
},
},
computed: {
filteredSheeps: function() {
var self = this;
return this.sheeps.filter(function(item) {
return item.family.toLowerCase().indexOf(self.search.toLowerCase()) > -1
})
}
}
}
}
</script>
我认为它需要filteredSheeps
中的计算方法v-for
,但事实并非如此。直接获得错误:
TypeError: null is not an object (evaluating 'item.family.toLowerCase')"
答案 0 :(得分:2)
这是一个计算方法,可以保护您免受未填充family
和/或name
的情况的影响。
filteredSheeps: function() {
let searchTerm = (this.search || "").toLowerCase()
return this.sheeps.filter(function(item) {
let family = (item.family || "").toLowerCase()
let name = (item.name || "").toLowerCase()
return family.indexOf(searchTerm) > -1 || name.indexOf(searchTerm) > -1
})
}
一个有效的例子。
console.clear()
const sheeps = [
{name: "Lily", type: "Dorper", family: "Family 1"},
{name: "Joe", type: "Merino", family: "Family 2"},
{name: "Bob", type: "Dorper", family: null},
]
new Vue({
el: "#app",
data:{
sheeps:[],
search: null
},
computed: {
filteredSheeps: function() {
let searchTerm = (this.search || "").toLowerCase()
return this.sheeps.filter(function(item) {
let family = (item.family || "").toLowerCase()
let name = (item.name || "").toLowerCase()
return family.indexOf(searchTerm) > -1 || name.indexOf(searchTerm) > -1
})
}
},
created(){
setTimeout(() => this.sheeps = sheeps, 500)
}
})
&#13;
<script src="https://unpkg.com/vue@2.4.2"></script>
<div id="app">
<input type="search" v-model="search" placeholder="Search for Name OR Family" />
<ul>
<li v-for="sheep in filteredSheeps">
{{ sheep.name }} ({{ sheep.type }}/{{ sheep.family }} )
</li>
</ul>
</div>
&#13;