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										 |  |  | --- | 
					
						
							|  |  |  | title: array | 
					
						
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										 |  |  | ## Introduction to PHP Array
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										 |  |  | An array can be thought of as a collection of items. | 
					
						
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										 |  |  | ## Syntax
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							|  |  |  | An array is defined by array(), or []. | 
					
						
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							|  |  |  | An example of an array in each style can be seen below: | 
					
						
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							|  |  |  | ``` | 
					
						
							|  |  |  | <?php | 
					
						
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							|  |  |  | $bikes = array('Suzuki','BMW','Yamaha'); | 
					
						
							|  |  |  | ``` | 
					
						
							|  |  |  | ``` | 
					
						
							|  |  |  | <?php | 
					
						
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							|  |  |  | $bikes = ['Suzuki', 'BMW', 'Yamaha']; | 
					
						
							|  |  |  | ``` | 
					
						
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							|  |  |  | ## Key => Value
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							|  |  |  | Arrays can also be defined with named keys, as shown below: | 
					
						
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							|  |  |  | ``` | 
					
						
							|  |  |  | <?php | 
					
						
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							|  |  |  | $bikes = [ | 
					
						
							|  |  |  |     'favorite'        => 'Suzuki', | 
					
						
							|  |  |  |     'second favorite' => 'BMW', | 
					
						
							|  |  |  |     'not my favorite' => 'Yamaha' | 
					
						
							|  |  |  | ]; | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | ## Accessing Items
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										 |  |  | Items within an array can be accessed by their corresponding key, or location within the array. | 
					
						
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										 |  |  | For instance: | 
					
						
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							|  |  |  | ``` | 
					
						
							|  |  |  | <?php | 
					
						
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										 |  |  | $bikes = ['Suzuki', 'BMW', 'Yamaha']; | 
					
						
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										 |  |  | echo 'I like '. $bikes[0]; | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | Would produce the following output: | 
					
						
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							|  |  |  | ``` | 
					
						
							|  |  |  | I like Suzuki | 
					
						
							|  |  |  | ``` | 
					
						
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							|  |  |  | Another example, using named keys can be seen below: | 
					
						
							|  |  |  | ``` | 
					
						
							|  |  |  | <?php | 
					
						
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							|  |  |  | $bikes = [ | 
					
						
							|  |  |  |     'favorite'        => 'Suzuki', | 
					
						
							|  |  |  |     'second favorite' => 'BMW', | 
					
						
							|  |  |  |     'not my favorite' => 'Yamaha' | 
					
						
							|  |  |  | ]; | 
					
						
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										 |  |  | echo 'I like '. $bikes['not my favorite']; | 
					
						
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										 |  |  | ``` | 
					
						
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							|  |  |  | Would produce the following output: | 
					
						
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							|  |  |  | ``` | 
					
						
							|  |  |  | I like BWM | 
					
						
							|  |  |  | ``` | 
					
						
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										 |  |  | ## Multidimensional Array
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							|  |  |  | As we mentioned earlier arrays are collection of items, often times these items may be arrays of themselves.  | 
					
						
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							|  |  |  | You will always be able to get the value for the specific key by going down the layers: $arr['layerOne']['two'] | 
					
						
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										 |  |  | ## Pitfalls
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							|  |  |  | When working with arrays, there are a few important things to keep in mind: | 
					
						
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							|  |  |  | 1) A comma after the last element is optional. | 
					
						
							|  |  |  | 2) Named keys must be escaped to be accessed (i.e. $bikes[not my favorite] would not work). | 
					
						
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							|  |  |  | For more information, please see [PHP: Arrays](http://php.net/manual/en/language.types.array.php) |