Php Array Method Summary--example is the truth

//1 Replace the key value size

$arr = Array (' a ' = = 1, ' b ' = = 2, ' C ' =>3, ' D ' + 4);         $lower = Array_change_key_case ($arr, case_lower);       $upper = Array_change_key_case ($arr, Case_upper);      Var_dump ($lower); Var_dump ($upper);

2 Divide the array into $size arrays, Haskay to preserve the original key value

$arr 2 = Array (' name ' = ' Lixueyao ', ' age ' = ', ' sex ' = ' f ');      $size = 2;     $hasKey = true;     $chunk = Array_chunk ($arr 2, $size, $hasKey); Var_dump ($chunk);

3 You can generate a new array with the key specified in a multidimensional array, and the 3rd parameter can be the key value of the new array

$arr 3s = array (' name ' = ' Lixueyao ', ' age ' = ' + ', ' sex ' = ' f '), Array (' name ' = = ' Zhang       San ', ' age ', ' sex ' = ' m '), Array (' name ' = ' = ' lisi ', ' age ' = ' + ', ' sex ' = ' f ');     $column = Array_column ($arr 3s, ' age ', ' name '); Print_r ($column);

4 combine two arrays, forming a new array of one as value, one as key

$arrCombineOne = Array (' One ', ' one ', ' one ', ' three ');     $arrCombineTwo = Array (' 1 ', ' 2 ', ' 3 ');     $combine = Array_combine ($arrCombineTwo, $arrCombineOne); Print_r ($combine);

5 returns the number of occurrences of value in the array

$arrValue = Array (' C ', ' d ', ' a ', ' C ', ' V ');     $arrcnt = Array_count_values ($arrValue); Print_r ($ARRCNT);

//6 compares the difference set of the array value, the one and the parameter comparisons, and the difference between the non-existent in the same array (in the same and the other, the other is the array of comparisons)
If multiple arrays are compared, it is the difference set of 3 arrays. (You can compare multiple arrays)

$arrDiffOne = Array (' a ' = = ' red ', ' b ' = = ' blue ', ' c ' = ' black ', ' d ' = ' = ' ' purple ');     $arrDiffTwo = Array (' a ' = = ' red ', ' b ' = ' blue ', ' n ' = ' black ',);     $arrDiffThree = Array (' a ' + = ' red ', ' f ' = = ' Hello ', ' c ' = ' black ');     $arrDiff = Array_diff ($arrDiffOne, $arrDiffTwo, $arrDiffThree); Print_r ($arrDiff)

;

7 Compare the array's key and value (all the same), one is the array to be compared
If it is 3 arrays to compare, you can compare the two groups, and then use other arrays to compare the difference between the first two groups

$ARRASSOC = Array_diff_assoc ($arrDiffOne, $arrDiffTwo, $arrDiffThree); Print_r ($ARRASSOC);

8 Comparing the key value of an array, same principle

$a 4 = array (' d ' = = ' name ');     $arrKey = Array_diff_key ($arrDiffOne, $arrDiffTwo, $arrDiffThree, $a 4); Print_r ($arrKey);

 
 

  $uassocOne  = array (' name '  =>  ' Zsy ',  ' age ' =>24,  ' say '  =>   ' Hello ');      $uassocTwo  = array (' name '  =>  ' Lixueyao ',   ' age '  => 24);      function myfunction ($a  ,  $b)      {          $res  = null;          if ($a  ===  $b)           {              $res  = 0;         }           $res  =  ($a < $b)  ? 1:-1;           return  $res;     }      $arrUassoc  = array_diff_uassoc ($uassocOne, &NBSP; $uassocTwo,  ' myfunction ');      print_r ($ARRUASSOC); 

10 comparison Key

function Mydiffkey ($a, $b) {if ($a = = = $b) {return 0;          } return ($a > $b)? 1:-1;         } $result =array_diff_ukey ($uassocOne, $uassocTwo, "Mydiffkey"); Print_r ($result);

Php Array Method Summary--example is the truth