0a1eeea424
* fix: replace sh with shell fix replace terminal with shell fix replace node with js fix replace output with shell fix replace cs with csharp fix replace c++ with cpp fix replace c# with csharp fix replace javasctipt with js fix replace syntax with js fix replace unix with shell fix replace linux with shell fix replace java 8 with java fix replace swift4 with swift fix replace react.js with jsx fix replace javascriot with js fix replace javacsript with js fix replace c++ - with cpp fix: corrected various typos fix: replace Algorithm with nothing fix: replace xaml with xml fix: replace solidity with nothing fix: replace c++ with cpp fix: replace txt with shell fix: replace code with json and css fix: replace console with shell
1012 B
1012 B
title, localeTitle
| title | localeTitle |
|---|---|
| Use a Ternary Expression for Conditional Rendering | 使用三元表达式进行条件渲染 |
使用三元表达式进行条件渲染
这个挑战是仅使用三元表达而不是在代码中使用If/Else ，
暗示
三元运算符有三个部分，但您可以将几个三元表达式组合在一起。这是基本语法：
condition ? expressionIfTrue : expressionIfFalse
解
这是使用三元表达的示例解决方案。 首先，您需要在构造函数中声明状态，如下所示
constructor(props) {
super(props);
// change code below this line
this.state = {
input: '',
userAge: ''
}
// change code above this line
this.submit = this.submit.bind(this);
this.handleChange = this.handleChange.bind(this);
}
然后是三元运算符
{
/* change code here */
(this.state.userAge >= 18) ? buttonTwo : (this.state.userAge== '')? buttonOne: buttonThree
}