PHP array sorting (ascending, descending, and related issues)

$a = Array (4, "37", 3,100,0,-5); Sort ($a); for ($i =0; $i <6; + + $i) { echo $a [$i]. " "; } echo " "; Sort ($a, sort_string); for ($i =0; $i <6; + + $i) { echo $a [$i]. " "; } echo " "; ?> Copy Code Output Result:-5 0 3 4 37 100-5 0 100 3 37 4 Sort Descending: Rsort (array, [sort type]) parameter usage is the same as the sort function. Associative array Ordering: functions: Asort (array, [Sort type]) Description: Sort Ascending According to the element values of the associative array. The parameters are used in the sort function above. Function: Ksort (array, [Sort type]) Description: Sort Ascending According to the keyword of the associative array. The parameters are used in the sort function above. $a = Array ( "Good" = "bad", "Right" = "wrong", "Boy" = "girl"); echo "Value sort "; Asort ($a); foreach ($a as $key = = $value) { echo "$key: $value "; } echo " Key sort "; Ksort ($a); foreach ($a as $key = = $value) { echo "$key: $value "; } ?> Copy Code Output Result: Value sort Good:bad boy:girl right:wrong Key sort Boy:girl Good:bad right:wrong descending sort: arsort (array, [sort type]) corresponds to Asort (array, [Sort type]) with Krsort Corresponding Quickly create an array of functions range () For example, the range () function can quickly create arrays of numbers from 1 to 9: $numbers =range (1,9); echo $numbers [1]; ?> Copy Code Of course, using range (9,1) creates an array of numbers from 9 to 1. Also, range () can create an array of characters from A to Z: $numbers =range (a,z); foreach ($numbers as $mychrs) echo $mychrs. " "; ?> Copy Code Note the case when using a character array, such as range (A,Z) and range (A,Z) are not the same. The range () function also has a third argument that sets the step size, such as the array elements created by range (1,9,3): 1, 4, 7. Common PHP array sorting the elements in a general array are represented by characters or numbers, so you can sort the elements in ascending order, the function is sort (). Like what: $people =array (' name ', ' Sex ', ' nation ', ' birth '); foreach ($people as $mychrs) echo $mychrs. " "; Sort ($people); echo " After---sort--- "; foreach ($people as $mychrs) echo $mychrs. " "; ?> Copy Code An ascending sorted array element is displayed as birth name Nation sex, of course, the sort () function is case-sensitive (Letters from the largest to smallest order are: A ... Z...A...Z) The sort () function also has a second parameter, which is used to indicate whether the rule in ascending order of the PHP array is to compare numbers or strings. Like what: echo "---sorted in ascending order of numbers--- "; $num 2=array (' 26 ', ' 3 ',); Sort ($num 2,sort_numeric); foreach ($num 2 as $mychrs) echo $mychrs. " "; echo " ---ordered by word Fu Shen--- "; $num 3=array (' 26 ', ' 3 '); Sort ($num 3,sort_string); foreach ($num 3 as $mychrs) echo $mychrs. " "; ?> Copy Code Sort_numeric and sort_string are used to declare in ascending order of numbers or characters. If the numbers are sorted in ascending order: 3, 26, but if ordered by word Fu Shen: 26, 3. In addition to the ascending function in PHP, there are functions in descending or reverse order, that is, the Rsort () function, such as: $num 1=range (1,9), Rsort ($num 1), which is actually equivalent to range (9,1). The contents of the ordering of the PHP array are finished, I wish you a happy study. >>> For more information, check out the PHP array sorting method Daquan <<<

