javascript - 如何将多个 else if 语句转换为三元运算符

Question

我如何将此if/else语句转换为三元运算符而不是使用if/else语句。我知道这对于大多数 JavaScript 开发人员来说很简单，但对我来说却很困惑。

  if(this.props.usersWhoAreTyping.length === 0) {
        return null
  } else if(this.props.usersWhoAreTyping.length === 1 ){
      return <p>{this.props.usersWhoAreTyping[0]} is typing...</p>
  }
   else if(this.props.usersWhoAreTyping.length > 1){
        return <p>{this.props.usersWhoAreTyping.join('and')} are typing...</p>
  }

我的尝试是这样的

 {this.props.usersWhoAreTyping.length === 0 ?  (
          null
 ): (
     <p>{this.props.usersWhoAreTyping[0]} is typing...</p>
 )}
 // not sure how to include the 2nd else if statement in this ternary operator 

Answer 1

如果我正确理解你的意图，就不需要三元组。

示例:

render() {
const { usersWhoAreTyping } = this.props

return (
   <div>
    {usersWhoAreTyping.length === 1 && <p>{usersWhoAreTyping[0]} is typing...</p>}
    {usersWhoAreTyping.length > 1 && <p>{usersWhoAreTyping.join('and')} are typing...</p>}
   </div>
)