99 lines
2.3 KiB
Markdown
99 lines
2.3 KiB
Markdown
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---
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id: 567af2437cbaa8c51670a16c
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title: Testing Objects for Properties
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c6Wz4ySr'
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forumTopicId: 18324
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dashedName: testing-objects-for-properties
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---
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# --description--
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Sometimes it is useful to check if the property of a given object exists or not. We can use the `.hasOwnProperty(propname)` method of objects to determine if that object has the given property name. `.hasOwnProperty()` returns `true` or `false` if the property is found or not.
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**Example**
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```js
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var myObj = {
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top: "hat",
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bottom: "pants"
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};
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myObj.hasOwnProperty("top");
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myObj.hasOwnProperty("middle");
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```
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The first `hasOwnProperty` returns `true`, while the second returns `false`.
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# --instructions--
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Modify the function `checkObj` to test if an object passed to the function (`obj`) contains a specific property (`checkProp`). If the property is found, return that property's value. If not, return `"Not Found"`.
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# --hints--
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`checkObj({gift: "pony", pet: "kitten", bed: "sleigh"}, "gift")` should return the string `pony`.
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```js
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assert(
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checkObj({ gift: 'pony', pet: 'kitten', bed: 'sleigh' }, 'gift') === 'pony'
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);
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```
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`checkObj({gift: "pony", pet: "kitten", bed: "sleigh"}, "pet")` should return the string `kitten`.
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```js
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assert(
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checkObj({ gift: 'pony', pet: 'kitten', bed: 'sleigh' }, 'pet') === 'kitten'
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);
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```
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`checkObj({gift: "pony", pet: "kitten", bed: "sleigh"}, "house")` should return the string `Not Found`.
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```js
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assert(
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checkObj({ gift: 'pony', pet: 'kitten', bed: 'sleigh' }, 'house') ===
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'Not Found'
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);
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```
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`checkObj({city: "Seattle"}, "city")` should return the string `Seattle`.
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```js
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assert(checkObj({ city: 'Seattle' }, 'city') === 'Seattle');
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```
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`checkObj({city: "Seattle"}, "district")` should return the string `Not Found`.
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```js
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assert(checkObj({ city: 'Seattle' }, 'district') === 'Not Found');
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```
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`checkObj({pet: "kitten", bed: "sleigh"}, "gift")` should return the string `Not Found`.
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```js
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assert(checkObj({ pet: 'kitten', bed: 'sleigh' }, 'gift') === 'Not Found');
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```
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# --seed--
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## --seed-contents--
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```js
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function checkObj(obj, checkProp) {
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// Only change code below this line
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return "Change Me!";
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// Only change code above this line
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}
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```
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# --solutions--
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```js
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function checkObj(obj, checkProp) {
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if(obj.hasOwnProperty(checkProp)) {
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return obj[checkProp];
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} else {
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return "Not Found";
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}
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}
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```
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