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---
id: 5a24c314108439a4d4036185
title: Use & & for a More Concise Conditional
challengeType: 6
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forumTopicId: 301413
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dashedName: use--for-a-more-concise-conditional
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---
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# --description--
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The `if/else` statements worked in the last challenge, but there's a more concise way to achieve the same result. Imagine that you are tracking several conditions in a component and you want different elements to render depending on each of these conditions. If you write a lot of `else if` statements to return slightly different UIs, you may repeat code which leaves room for error. Instead, you can use the `&&` logical operator to perform conditional logic in a more concise way. This is possible because you want to check if a condition is `true` , and if it is, return some markup. Here's an example:
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```jsx
{condition & & < p > markup< / p > }
```
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If the `condition` is `true` , the markup will be returned. If the condition is `false` , the operation will immediately return `false` after evaluating the `condition` and return nothing. You can include these statements directly in your JSX and string multiple conditions together by writing `&&` after each one. This allows you to handle more complex conditional logic in your `render()` method without repeating a lot of code.
# --instructions--
Solve the previous example again, so the `h1` only renders if `display` is `true` , but use the `&&` logical operator instead of an `if/else` statement.
# --hints--
`MyComponent` should exist and render.
```js
assert(
(function () {
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
return mockedComponent.find('MyComponent').length;
})()
);
```
When `display` is set to `true` , a `div` , `button` , and `h1` should render.
```js
async () => {
const waitForIt = (fn) =>
new Promise((resolve, reject) => setTimeout(() => resolve(fn()), 250));
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
const state_1 = () => {
mockedComponent.setState({ display: true });
return waitForIt(() => mockedComponent);
};
const updated = await state_1();
assert(
updated.find('div').length === 1 & &
updated.find('div').children().length === 2 & &
updated.find('button').length === 1 & &
updated.find('h1').length === 1
);
};
```
When `display` is set to `false` , only a `div` and `button` should render.
```js
async () => {
const waitForIt = (fn) =>
new Promise((resolve, reject) => setTimeout(() => resolve(fn()), 250));
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
const state_1 = () => {
mockedComponent.setState({ display: false });
return waitForIt(() => mockedComponent);
};
const updated = await state_1();
assert(
updated.find('div').length === 1 & &
updated.find('div').children().length === 1 & &
updated.find('button').length === 1 & &
updated.find('h1').length === 0
);
};
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```
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The render method should use the `&&` logical operator to check the condition of `this.state.display` .
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```js
(getUserInput) => assert(getUserInput('index').includes('&&'));
```
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# --seed--
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## --after-user-code--
```jsx
ReactDOM.render(< MyComponent / > , document.getElementById('root'))
```
## --seed-contents--
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```jsx
class MyComponent extends React.Component {
constructor(props) {
super(props);
this.state = {
display: true
}
this.toggleDisplay = this.toggleDisplay.bind(this);
}
toggleDisplay() {
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this.setState(state => ({
display: !state.display
}));
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}
render() {
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// Change code below this line
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return (
< div >
< button onClick = {this.toggleDisplay} > Toggle Display< / button >
< h1 > Displayed!< / h1 >
< / div >
);
}
};
```
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# --solutions--
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```jsx
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class MyComponent extends React.Component {
constructor(props) {
super(props);
this.state = {
display: true
}
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this.toggleDisplay = this.toggleDisplay.bind(this);
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}
toggleDisplay() {
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this.setState(state => ({
display: !state.display
}));
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}
render() {
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// Change code below this line
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return (
< div >
< button onClick = {this.toggleDisplay} > Toggle Display< / button >
{this.state.display & & < h1 > Displayed!< / h1 > }
< / div >
);
}
};
```