55 lines
1.2 KiB
Markdown
55 lines
1.2 KiB
Markdown
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---
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title: Check if an Object has a Property
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---
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## Check if an Object has a Property
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Method:
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- The simplest way to complete this challenge is to create an `ìf-statement` to check wether or not the object contains all useres, then to return a true or false statement. The first solution does just this.
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- The second solution works in exactly the same way, only it uses 1 line of code - `Conditional(ternary)-Operator` - within the function.
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[developer.mozilla.org](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_Operator) provides a more in depth analysis of the ternary operator.
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### Solution-1:
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```javascript
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let users = {
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Alan: {
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age: 27,
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online: true
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},
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Jeff: {
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age: 32,
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online: true
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},
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Sarah: {
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age: 48,
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online: true
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},
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Ryan: {
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age: 19,
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online: true
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}
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};
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function isEveryoneHere(obj) {
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// change code below this line
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if(users.hasOwnProperty('Alan','Jeff','Sarah','Ryan')) {
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return true;
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}
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return false;
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// change code above this line
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}
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console.log(isEveryoneHere(users));
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```
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### Solution-2:
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```javascript
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function isEveryoneHere(obj) {
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return (users.hasOwnProperty('Alan','Jeff','Sarah','Ryan')) ? true : false;
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}
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```
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