React 使用 if else 判断语句
今天在写 React 时,在 render 的return中既然不能使用if判断语句,所以就整理一些在react中使用if 的方式,可根据自己的实际情况选择:
方式一:
class LLL extends React.Component {
constructor(props){
super(props);
this.judge = false
}
render(){
let Message
if (this.judge) {
Message = (
<span>
<h5>It`s my life!</h5>
</span>
)
} else {
Message = (
<h5>I think that's more than just like it!</h5>
)
}
return(
<div>
<h4>Wellcom LLL</h4>
{Message}
</div>
);
}
}
方式二:
class LLL extends React.Component {
constructor(props){
super(props);
this.judge = false
}
Message(){
if (this.judge) {
return (
<span>
<h5>It`s my life!</h5>
</span>
)
} else {
return (
<h5>I think that's more than just like it!</h5>
)
}
}
render(){
return(
//1
<div>
<h4>Wellcom LLL</h4>
{this.Message()}
</div>
);
}
}
方式三:三元运算符
class LLL extends React.Component {
constructor(props){
super(props);
this.judge = false
}
render(){
return(
//1
<div>
<h4>Wellcom LLL</h4>
{this.judge ? "It`s my life!" : "I think that's more than just like it!"}
</div>
);
}
}
方式四:
class LLL extends React.Component {
constructor(props){
super(props);
this.judge = false
}
render(){
return(
//1
<div>
<h4>Wellcom LLL</h4>
{
this.judge
?
<span>
<h5>It`s my life!</h5>
</span>
:
<h5>I think that's more than just like it!</h5>
}
</div>
);
}
}