Javascript - Array - Creating Array
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There are several ways to create an array in JavaScript: 1) Using square brackets to declare an empty array, 2) Declaring an array with a set of elements inside brackets, 3) Using the Array constructor to create an empty array or an array with elements, 4) Using the Array constructor to specify the length of an empty array. Arrays can contain elements of different types and the Array.isArray() function can verify if an object is an array.
![Arrays
• The simplest way to create an array is by
declaring an array variable using the []
operator.
• var myArray = []](https://image.slidesharecdn.com/javascript-array-creatingarray-150107193158-conversion-gate01/85/Javascript-Array-Creating-Array-2-320.jpg)
![Arrays
• When you create an array in this manner, you
have an array with length of 0.
var myArray = []
console.log(myArray.length);](https://image.slidesharecdn.com/javascript-array-creatingarray-150107193158-conversion-gate01/85/Javascript-Array-Creating-Array-3-320.jpg)
![Arrays
• Another way to create an array is to declare an
array variable with a set of elements inside
the [] operator:
var myArray = [1,2,3,5,9,7,0,-1];
console.log(myArray.length);](https://image.slidesharecdn.com/javascript-array-creatingarray-150107193158-conversion-gate01/85/Javascript-Array-Creating-Array-4-320.jpg)
![Arrays
• JavaScript array elements do not all have to be
of the same type:
var myArray = [‘5.2’, 38, “Samuel”, true, null];
console.log(myArray);](https://image.slidesharecdn.com/javascript-array-creatingarray-150107193158-conversion-gate01/85/Javascript-Array-Creating-Array-8-320.jpg)
![Arrays
• We can verify that an object is an array by
calling the Array.isArray() function, like this:
var myArray = [‘5.2’, 38];
var number = 66;
console.log(Array.isArray(myArray));
console.log(Array.isArray(number));](https://image.slidesharecdn.com/javascript-array-creatingarray-150107193158-conversion-gate01/85/Javascript-Array-Creating-Array-9-320.jpg)
Javascript - Array - Creating Array
- 2. Arrays • The simplest way to create an array is by declaring an array variable using the [] operator. • var myArray = []
- 3. Arrays • When you create an array in this manner, you have an array with length of 0. var myArray = [] console.log(myArray.length);
- 4. Arrays • Another way to create an array is to declare an array variable with a set of elements inside the [] operator: var myArray = [1,2,3,5,9,7,0,-1]; console.log(myArray.length);
- 5. Arrays • You can also create an array by calling the Array constructor: var myArray = new Array(); console.log(myArray.length); Array Constructor
- 6. Arrays • You can call the Array constructor with a set of elements as arguments to the constructor: var myArray = new Array(8, 9, 11, 13,5,2); console.log(myArray.length);
- 7. Arrays • Finally, you can create an array by calling the Array constructor with a single argument specifying the length of the array: var myArray = new Array(10); console.log(myArray.length);
- 8. Arrays • JavaScript array elements do not all have to be of the same type: var myArray = [‘5.2’, 38, “Samuel”, true, null]; console.log(myArray);
- 9. Arrays • We can verify that an object is an array by calling the Array.isArray() function, like this: var myArray = [‘5.2’, 38]; var number = 66; console.log(Array.isArray(myArray)); console.log(Array.isArray(number));