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