PHP - Array

There are two kinds of Array: Regular array(based on numeric index) and Associative array(Map collection in Java); In PHP, the size of array can grow - it's loosely.

To initialize an array, use one of the fallowing:

>> $cities = array("denpasar","manila","sydney");

or

>> $cities = array();

>> $cities[] = "denpasar";

>> $cities[] = "manila";

>> $cities[] = "sydney";

or

>> $names = array("steve"=>"jobs",

>>                "larry"=>"page",

>>                "sergey"=>"brin");

or

>> $names = array();

>> $names["steve"] = "jobs";

>> $names["larry"] = "page";

To get to know how many elements in an array, use:

>> $count = count($cities)    // return 3

To print out the structure of array use one either of:

>> print_r($cities);

>> var_dump($cities);

To make a new assoc array based on two regular array, use: $fname as key and $lname as value

>> $newAssocArray = array_combine($fname,$lname); 

To get key as an array from an assoc array, use:

>> $keyArray = array_keys($names);      
                      // result array("steve","larry","sergey")

To get value as an array from an assoc array, use:

>> $valueArray = array_values($names);
                     // result array("jobs","page","bin")

To reverse the array elements order, use:

>> array_reverse($cities); 

To sort an assoc arrays based on keys:

>> ksort($names);

To bind the elements of array to variables, use:

>> list($a,$b,$c) = $cities; 

For iterating through elements of array, use:

>> foreach($cities as $values){

>>     echo "$values <br>"

>> }

or

>> foreach($names as $keys=>$values){

>>     echo "$keys: $values <br>"

>> }

PHP - Array