JSX在render函数中的应用详解

const element = <h1>Hello, world!</h1>;

const element = (
 <h1 className="greeting">
  Hello, world!
 </h1>
);

const element = React.createElement(
 'h1',
 {className: 'greeting'},
 'Hello, world!'
);

const element = {
 type: 'h1',
 props: {
  className: 'greeting',
  children: 'Hello, world!'
 }
};

<Level :type="1">哈哈</Level>
<Level :type="2">哈哈</Level>
<Level :type="3">哈哈</Level>

<template>
 <h1 v-if="type==1">
 <slot></slot>
 </h1>
 <h2 v-else-if="type==2">
 <slot></slot>
 </h2>
 <h3 v-else-if="type==3">
 <slot></slot>
 </h3>
</template>
<script>
export default {
 props: {
 type: {
  type: Number
 }
 }
};
</script>

export default {
 render(h) {
 return h("h" + this.type, {}, this.$slots.default);
 },
 props: {
 type: {
  type: Number
 }
 }
};

export default {
 render(h) {
 const tag = "h" + this.type;
 return <tag>{this.$slots.default}</tag>;
 },
 props: {
 type: {
  type: Number
 }
 }
};

<List :data="data"></List>
<script>
import List from "./components/List";
export default {
 data() {
 return { 
  data: ["苹果", "香蕉", "橘子"] 
 };
 },
 components: {
 List
 }
};
</script>

<!-- List组件渲染列表 -->
<template>
 <div class="list">
 <ul v-for="(item,index) in data" :key="index">
  <li>{{item}}</li>
 </ul>
 </div>
</template>
<script>
export default {
 props: {
 data: Array,
 default: () => []
 }
};
</script>

<List :data="data" :render="render"></List>
render(h, name) {
  return <span>{name}</span>;
}

<template>
 <div class="list">
 <div v-for="(item,index) in data" :key="index">
  <li v-if="!render">{{item}}</li>
  <!-- 将render方法传到函数组件中，将渲染项传入到组件中，在内部回调这个render方法 -->
  <ListItem v-else :item="item" :render="render"></ListItem>
 </div>
 </div>
</template>
<script>
import ListItem from "./ListItem";
export default {
 components: {
 ListItem
 },
 props: {
 render: {
  type: Function
 },
 data: Array,
 default: () => []
 }
};
</script>

<script>
export default {
 props: {
 render: {
  type: Function
 },
 item: {}
 },
 render(h) {
 return this.render(h, this.item);
 }
};
</script>

<List :arr="arr">
  <template v-slot="{item}">
    {{item}}
  </template>
</List>

<div v-for="(item,key) in arr" :key="key">
  <slot :item="item"></slot>
</div>

<template>
<div>
 <Table :columns="columns" :data="data"></Table>
</div>
</template>
<script>
import Vue from 'vue';
export default {
 methods:{
  render(h,{column,index,row}){
   let value = row[column.key];
   return <div on-click={(e)=>this.changeIndex(e,index)} >
    {this.index === index ? 
     <i-input type="text" value={value} on-input={(value)=>{
      this.handleChange(value,column,row)
     }} onOn-enter={()=>this.enter(row,index)}/>:
     <span>{value}</span>
    }
   </div>
  },
  enter(row,index){
   this.data.splice(index,1,row);
   this.index = -1;
  },
  handleChange(value,column,row){
   row[column['key']]= value;
  },
  changeIndex(e,index){
   this.index = index;
   this.$nextTick(()=>{
    e.currentTarget.getElementsByTagName("input")[0].focus();
   })
  }
 },
 data() {
  return {
   index:-1,
   columns: [
    {
     title: 'Name',
     key: 'name',
     render:this.render
    },
    {
     title: 'Age',
     key: 'age',
    },
    {
     title: 'Address',
     key: 'address',
    },
   ],
   data: [
    {
     name: 'John Brown',
     age: 18,
     address: 'New York No. 1 Lake Park',
     date: '2016-10-03',
    },
    {
     name: 'Jim Green',
     age: 24,
     address: 'London No. 1 Lake Park',
     date: '2016-10-01',
    },
    {
     name: 'Joe Black',
     age: 30,
     address: 'Sydney No. 1 Lake Park',
     date: '2016-10-02',
    },
    {
     name: 'Jon Snow',
     age: 26,
     address: 'Ottawa No. 2 Lake Park',
     date: '2016-10-04',
    },
   ],
  };
 },
};
</script>