summary

Slots are used in subcomponents slot The reserved position defined by the label , You can set name attribute , It can also be set without name attribute , Set up name Call A named slot , Not set up name The name of Anonymous slot , When using a child component in a parent component, you can write to the named slot or unnamed slot in the child component by declaring or not declaring the slot name in the tag of the child component html Code .

The key to using slots is ： When using the child component tag in the parent component, you can write html Code .

Use steps

1. Slots are defined in the subcomponent
2. Write code to slot when parent component uses child component

When to use slots ？

Just a chestnut ： Yes 2 A component , Parent component father, Child components son.

Parent component father

<template>
<div>
<h3> This is the parent component </h3>
<son> practice slot</son>
</div>
</template>

Child components son

<template>
<div>
<h4> This is the subcomponent </h4>
<input type="text" placeholder=" Please enter ">
</div>
</template>

In general, our components will write , But in this way , You'll find the practice in the subcomponents slot It doesn't show . If you need him to show it , Now we can use slots slot 了 .

How to use slots ？

First , We're going to add slots to the subcomponents slot,

<template>
<div>
<h4> This is the subcomponent </h4>
<input type="text" placeholder=" Please enter ">
<slot></slot>
</div>
</template>

At this time , At last slot.slot Will appear in the parent component practice slot These big words .

You can see , Inside this slot There is no name , seeing the name of a thing one thinks of its function , This is the default slot in the slot .

And then look at the named slot , Go straight to the code .
Parent component

<template>
<div>
<h3> This is the parent component </h3>
<son><span> practice slot</span></son>
<son>
<template slot="myslot">
<div>
Practice naming slot
</div>
</template>
</son>
</div>
</template>

Child components

<template>
<div>
<h4> This is the subcomponent </h4>
<input type="text" placeholder=" Please enter ">
<slot></slot>
<slot name="myslot"></slot>
</div>
</template>

It can be seen that , Unlike the default slot , In the child component , We give the slot a name attribute , This is the name of the slot , At the same time, in the parent component , We've added a tag to the place where the content needs to be inserted slot attribute , His value is ours slot name name.

So let's see slot-scope.
slot-scope Is the scope slot .

There is a special emphasis on the official website ： Everything in the parent component template is compiled in the parent scope ; Everything in the subcomponent template will be compiled within the scope of the subcomponent . To put it simply , That is, the parent component cannot be defined directly in the child component data data . and slot-scope The emergence of the problem is to solve such a problem .

Parent component

<template lang="">
<div>
<h3> This is the parent component </h3>
<son>
<template slot="myslot" slot-scope="scope">
<ul>
<li v-for="item in scope.data">
{
{item}}
</li>
</ul>
</template>
</son>
</div>
</template>

Child components

<template>
<div>
<h4> This is the subcomponent </h4>
<input type="text" placeholder=" Please enter ">
<slot name="myslot" :data='list'></slot>
</div>
</template>
<script>
export default {
name:'Son',
data(){
return{
list:[
{name:"Tom",age:15},
{name:"Jim",age:25},
{name:"Tony",age:13}
]
}
}
}
</script>

among , The values of the three objects below , We are defined in the subcomponent itself , According to the official document , Originally, the data cannot be displayed in the parent component , But why does it show up now ？ This is due to our powerful slot-scope 了 .

First , There's a sentence on the slot in the subcomponent data=“list”, And in the parent component, there are slot-scope=“scope”,slot-scope Is to take data Value ,slot-scope The value of is custom , We can take any name , however data The value of is passed in the form of Objects form Transmission of , So here scope.data It's just list Value .

In this way, we can get the value of the child component in the parent component , And applied it .

notes

1. from vue2.6.0 Start ,slot、slot-scope Has been abandoned , Recommended v-slot; On the difference of usage between the two , Please move to blog 《Vue Advanced （ One twenty-eight ）：Vue slot ：slot、slot-scope And instructions v-slot Use different ways to explain 》.