90 lines
2.7 KiB
Markdown
90 lines
2.7 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244c7
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title: Accessing Object Properties with Dot Notation
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localeTitle: Acceso a las propiedades del objeto con notación de puntos
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challengeType: 1
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---
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## Description
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<section id='description'>
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Hay dos formas de acceder a las propiedades de un objeto: notación de puntos ( <code>.</code> ) Y notación de corchetes ( <code>[]</code> ), similar a una matriz.
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notación de puntos es lo que usa cuando conoce el nombre de la propiedad a la que intenta acceder con anticipación.
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Aquí hay una muestra de cómo usar la notación de puntos ( <code>.</code> ) Para leer la propiedad de un objeto:
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<blockquote>var myObj = {<br> prop1: "val1",<br> prop2: "val2"<br>};<br>var prop1val = myObj.prop1; // val1<br>var prop2val = myObj.prop2; // val2</blockquote>
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</section>
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## Instructions
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<section id='instructions'>
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Lea los valores de propiedad de <code>testObj</code> usando la notación de puntos. Establezca la variable <code>hatValue</code> igual al <code>hat</code> propiedad del objeto y establezca la variable <code>shirtValue</code> igual a la <code>shirt</code> propiedad del objeto.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>hatValue</code> debe ser una cadena
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testString: 'assert(typeof hatValue === "string" , "<code>hatValue</code> should be a string");'
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- text: El valor de <code>hatValue</code> debe ser <code>"ballcap"</code>
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testString: 'assert(hatValue === "ballcap" , "The value of <code>hatValue</code> should be <code>"ballcap"</code>");'
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- text: <code>shirtValue</code> debe ser una cadena
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testString: 'assert(typeof shirtValue === "string" , "<code>shirtValue</code> should be a string");'
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- text: El valor de <code>shirtValue</code> debe ser <code>"jersey"</code>
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testString: 'assert(shirtValue === "jersey" , "The value of <code>shirtValue</code> should be <code>"jersey"</code>");'
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- text: Deberías usar la notación de puntos dos veces.
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testString: 'assert(code.match(/testObj\.\w+/g).length > 1, "You should use dot notation twice");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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// Setup
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var testObj = {
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"hat": "ballcap",
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"shirt": "jersey",
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"shoes": "cleats"
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};
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// Only change code below this line
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var hatValue = testObj; // Change this line
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var shirtValue = testObj; // Change this line
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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console.info('after the test');
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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var testObj = {
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"hat": "ballcap",
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"shirt": "jersey",
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"shoes": "cleats"
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};
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var hatValue = testObj.hat;
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var shirtValue = testObj.shirt;
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```
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</section>
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