2018-10-12 15:37:13 -04:00
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---
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title: Check For The Presence of an Element With indexOf()
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---
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## Check For The Presence of an Element With indexOf()
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- A simple `if-statement` can be used to check whether or not the value returned by the `indexOf()` function is less than 0.
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- Once the value is discovered then you can return either `true` or `false`.
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- `Solution-1` demonstrates how a simple `if-statement` can return the correct result.
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## Solution-1:
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```javascript
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function quickCheck(arr, elem) {
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if(arr.indexOf(elem)>=0) {
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return true;
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}
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return false;
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}
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console.log(quickCheck(['squash', 'onions', 'shallots'], 'mushrooms'));
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```
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- `Solution-2` demonstrates how the problem can be solved using the `? : (conditional)` operator.
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## Solution-2:
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```javascript
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function quickCheck(arr, elem) {
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return arr.indexOf(elem) >= 0 ? true : false;
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}
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console.log(quickCheck(['squash', 'onions', 'shallots'], 'mushrooms'));
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```
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2018-11-22 22:14:40 +01:00
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- `Solution-3` demonstrates how the problem can be solved by directly returning result of the comparison.
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## Solution-3:
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```javascript
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function quickCheck(arr, elem) {
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return arr.indexOf(elem) != -1;
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}
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console.log(quickCheck(['squash', 'onions', 'shallots'], 'mushrooms'));
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```
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