PHP basic Function Summary _php tips

1. Count the number of elements in an array

$arr = Array (
   ' 1011,1003,1008,1001,1000,1004,1012 ', '
   1009 ', ' 1011,1003,1111 '
  );
$result = Array ();
foreach ($arr as $str) {
 $str _arr = Explode (', ', $str);
 foreach ($str _arr as $v) {
  //$result [$v] = Isset ($result [$v])? $result [$v]: 0;
  $result [$v] = $result [$v] + 1;
  $result [$v] = Isset ($result [$v])? $result [$v]+1:1;
 }
}
Print_r ($result);
Array
(
[1011] => 2
[1003] => 2
[1008] => 1
[1001] => 1
[1000] => 1
[1004] => 1
[1012] => 1
[1009] => 1
[1111] => 1
)

2. Cycle Delete Directory

function Cleanup_directory ($dir) {
 foreach (new Directoryiterator ($dir) as $file) {
  if ($file->isdir ()) { C31/>if (! $file->isdot ()) {
    cleanup_directory ($file->getpathname ());
   }
  } else {
    unlink ($ File->getpathname ());
  }
  RmDir ($dir);

3. Infinite Polar classification Spanning tree

function Generatetree ($items) {$tree = array (); foreach ($items as $item) {if (Isset ($items [$item [' pid ']]) {$items [$item [' pid ']][' son '] [] = & $items [' ID
    ']];
    }else{$tree [] = & $items [$item [' id ']];
} return $tree; The function generateTree2 ($items) {foreach ($items as $item) $items [$item [' pid ']][' son '] [$item [' id ']] = & $items [$i
  tem[' id ']]; return Isset ($items [0][' son '])?
$items [0][' son ']: Array (); $items = Array (1 => array (' ID ' => 1, ' pid ' => 0, ' name ' => ' Anhui Province '), 2 => array (' ID ' => 2, ' pid ' = > 0, ' name ' => ' Zhejiang province ', 3 => array (' ID ' => 3, ' pid ' => 1, ' name ' => ' Hefei '), 4 => array (' ID ' =>
4, ' PID ' => 3, ' name ' => ' Changfeng County '), 5 => array (' ID ' => 5, ' pid ' => 1, ' name ' => ' Anqing '),);
Print_r (Generatetree ($items));
/** * How to take data formatted tree data/$tree = Generatetree ($items); function Gettreedata ($tree) {foreach ($tree as $t) {echo $t [' name ']. '
    <br> '; if (Isset ($t [' SoN ']) {gettreedata ($t [' son ']);

 }
  }
}

4. Array sort A-b is a numeric array. When you encounter a string, you need to

var test = [' ab ', ' AC ', ' BD ', ' BC '];
Test.sort (function (A, b) {
  if (a < b) {
    return-1
  }

  if (a > B) {return
    1;
  }

  return 0;
});

5.array_reduce

$raw = [1,2,3,4,5,];
The third parameter of the array_reduce is the initial value of the $result
array_reduce ($raw, function ($result, $value) {
  $result [$value] = $value; return

  $result;
}, []);
[1 => 1, 2 => 2, ... 5 => 5]

Only one or more parameters are accepted in the 6.array_map closure, the number of parameters of the closure and the number of parameters of the Array_map itself must be the same

$input = [' key ' => ' value '];
Array_map (function ($key, $value) {

  echo $key. $value;
}, Array_keys ($input), $input)
//' keyvalue '
$double = function ($item) {return
 2 * $item;
}

$result = Array_map ($double, [1,2,3]);

2 4 6

7. Breeding Rabbits

$month =;
  $fab = Array ();

  $fab [0] = 1;
  $fab [1] = 1;

   for ($i = 2; $i < $month; $i + +)
   {
     $fab [$i] = $fab [$i-1] + $fab [$i-2];
   }

   for ($i = 0; $i < $month; $i + +)
   {
     echo sprintf ("{%d} month rabbit is: {%d}", $i, $fab [$i]). " <br/> ";
   }

8. DateTime

function Getcurmonthfirstday ($date)
{return
  date (' y-m-01 ', Strtotime ($date));
}
 Getcurmonthlastday (' 2015-07-23 ')
function Getcurmonthlastday ($date)
{return
  date (' y-m-d ', Strtotime date (' y-m-01 ', Strtotime ($date)). ' +1 month-1 Day ');
}

9. Encrypt and decrypt

function Encrypt ($data, $key) {$key = MD5 ($key);
  $x = 0;
  $len = strlen ($data);
  $l = strlen ($key);
  $char = ';
    for ($i = 0; $i < $len; $i + +) {if ($x = = $l) {$x = 0;
    $char. = $key {$x};
  $x + +;
  } $str = ';
  for ($i = 0; $i < $len; $i + +) {$str. = Chr (Ord ($data {$i}) + (Ord ($char {$i}))% 256);
Return Base64_encode ($STR);
  function Decrypt ($data, $key) {$key = MD5 ($key);
  $x = 0;
  $data = Base64_decode ($data);
  $len = strlen ($data);
  $l = strlen ($key);
  $char = ';
    for ($i = 0; $i < $len; $i + +) {if ($x = = $l) {$x = 0;
    $char. = substr ($key, $x, 1);
  $x + +;
  } $str = ';  for ($i = 0; $i < $len; $i + +) {if Ord (substr ($data, $i, 1)) < Ord (substr ($char, $i, 1)) {$str. =
    Chr (Ord (substr ($data, $i, 1)) + 256)-Ord (substr ($char, $i, 1)));
    else {$str. = Chr (Ord (substr ($data, $i, 1))-Ord (substr ($char, $i, 1));
  }
  }return $str;

 }

10. Multidimensional Array demotion

function Array_flatten ($arr) {$result = [];
  Array_walk_recursive ($arr, function ($value) use (& $result) {$result [] = $value;

  });
return $result; } print_r (Array_flatten ([1,[2,3],[4,5]))//[1,[2,3],[4,5]] => [1,2,3,4,5]//var New_array = Old_array.concat ( value1[, value2[, ...
[, Valuen]]]
var test = [1,2,3,[4,5,6],[7,8]]; [].concat.apply ([], test); [1,2,3,4,5,6,7,8] concat it into an empty array [] for each value in the test array, and because Concat is the prototype of the array, we use an empty array as the carrier Var tes

T1 = [1,2,[3,[4,[5]]]]; function Flatten (arr) {return arr.reduce (function (pre, cur) {if (Array.isarray (cur)) {return Flatten (Pre.con
    Cat (cur));
  return Pre.concat (cur);
}, []); }//[1,2,3,4,5] json_encode Chinese function json_encode_wrapper ($result) {if (Defined (' Json_unescaped_unicode ')) {Retu RN Json_encode ($result, json_unescaped_unicode|
  Json_numeric_check);
}else {return preg_replace ("#\\\u ([0-9a-f][0-9a-f][0-9a-f][0-9a-f]) #ie", "/\" (\d+) \ "/",),      Array ("Iconv" (' UCS-2 ', ' UTF-8 ', pack (' H4 ', ' \\1 ')) "," \\1 "), Json_encode ($result));

 }
}

12. Two-d array to heavy

 $arr = Array (array (' ID ' => ' 2 '), ' title ' => ' ... ', ' ding ' => ' 1 ', ' Jing ' => ' 1 ', ' Time ' => ' ... ', ' url ' => ' ... ', ' DJ ' => ' ... '), array (' ID ' => ' 2 ', ' title ' => ' ... ', ' ding ' => ' 1 ', ' jing ' =
> ' 1 ', ' time ' => ' ... ', ' url ' => ' ... ', ' DJ ' => ' ... '); function About_unique ($arr =array ()) {/* is the two-dimensional array as a one-dimensional array, then the value value of the one-dimensional array is the same, the kill leaves only one, and the one-dimensional array is returned with the rearrangement indexed array, and each element in the returned one-dimensional array
  is an associative array of the original key value * * * $keys =array ();
  $temp = Array ();
  foreach ($arr [0] as $k => $arrays) {///* The key value of the associative array under record/* =/$keys [] = $k;  }//return $keys;
  /* Descending dimension/foreach ($arr as $k => $v) {$v = join (",", $v);//Descending dimension $temp [] = $v; } $temp = Array_unique ($temp); 
  Remove duplicate content foreach ($temp as $k => $v) {/* re-assemble the disassembled array by index array * * $temp [$k] = Explode (",", $v);  }//return $temp; /* The disassembled array is reassembled by associative array key value/foreach ($temp as $k => $v) {foreach ($v as $kkk => $ck) {$data [$k] [$keys [$kkk]] = $temp [$k]
  [$KKK];
 } return $data; }

13. Format Byte size

/**
* Format byte size
* @param   number $size bytes
* @param string $delimiter number and unit separator
* @return string      Formatted size with unit
* @author
/function Format_bytes ($size, $delimiter = ') {
 $units = array (' B ', ' KB ', ' MB ') , ' GB ', ' TB ', ' PB ');
 for ($i = 0; $size >= 1024 && $i < 6; $i + +) $size/= 1024;
 Return round ($size, 2). $delimiter. $units [$i];
}

14.3 minutes ago.

/**
* Converts the specified timestamp to the format that is before the current XX time such as return ' 3 minutes ago '
@param string|int $timestamp unix Timestamp
* @return String
* /
function Time_ago ($timestamp) {
  $etime = time ()-$timestamp;
  if ($etime < 1) return ' just ';   
  $interval = Array (* *     
   => ' (' y-m-d ', $timestamp) (') ') ', * * * *    =&G T ' A month ago ('. Date (' m-d ', $timestamp). ') ',
   7 *    => ' Week ('. Date (' m-d ', $timestamp). ') ',
   24 * 60 * 6 0      => ' days ago ',         => ' hours ago ',           => ' minutes ago ',
   1            => ' seconds ago '
  );
  foreach ($interval as $secs => $str) {
    $d = $etime/$secs;
    if ($d >= 1) {
      $r = round ($d);
      Return $r. $str;}}
  ;

15. ID Number

/** * Determine if the parameter string is a celestial ID number * @param $id a string or number that needs to be judged * @return mixed false or array[the content array Boolean is true]/function is_citize
  N_ID ($id) {//The length of the 18-digit ID is uppercase $id = Strtoupper ($id); if (!) ( Preg_match ('/^\d{17} (\d| X) $/', $id) | |
  Preg_match ('/^\d{15}$/', $id))) {return false; 
  }///15 digits converted to 18 bits and converted to string $Wi = Array (7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8); 
  $Ai = Array (' 1 ', ' 0 ', ' X ', ' 9 ', ' 8 ', ' 7 ', ' 6 ', ' 5 ', ' 4 ', ' 3 ', ' 2 ');
  $cardNoSum = 0; if (strlen ($id) ==16) {$id = substr (0, 6). ' 
    SUBSTR (6, 9);
    for ($i = 0; $i < $i + +) {$cardNoSum + + substr ($id, $i, 1) * $Wi [$i]; 
    $seq = $cardNoSum% 11;
  $id = $id. $Ai [$SEQ];
  The validity of the last character of the 18-digit ID card $cardNoSum = 0;
  $id = substr ($id, 0,17);
  $lastString = substr ($id, 17, 1);
  for ($i = 0; $i < $i + +) {$cardNoSum + + substr ($id, $i, 1) * $Wi [$i];
  $seq = $cardNoSum% 11;
  $realString = $Ai [$seq];
  if ($lastString!= $realString) {return false;} ToDomain Efficacy $oCity = array (11=> "Beijing",12=> "Tianjin",13=> "Hebei",14=> "Shanxi",15=> "Inner Mongolia",21=> "Liaoning",22=> "Jilin",23=> " Heilongjiang ",31=>" "Shanghai",32=> "Jiangsu",33=> "Zhejiang",34=> "Anhui",35=> "Fujian",36=> "Jiangxi",37=> "Shandong",41=> "Henan",42=> " Hubei ",43=>" Hunan ",44=>" Guangdong ",45=>" Guangxi ",46=>" Hainan ",50=>" Chongqing ",51=>" Sichuan ",52=>" Guizhou ",53=>" Yunnan ",54=>" Tibet ",61=>" Shaanxi ",62=>" Gansu ",63=>" Qinghai ",64=>" Ningxia ",65=>" Xinjiang ",71=>" Taiwan ",81=>" Hong Kong ",82=>" Macao ",91=>" foreign ")
  ;
  $City = substr ($id, 0, 2);
  $BirthYear = substr ($id, 6, 4);
  $BirthMonth = substr ($id, 10, 2);
  $BirthDay = substr ($id, 12, 2); $Sex = substr ($id, 16,1)% 2//male 1 female 0//$SEXCN = $Sex? '
  Male ': ' Female ';
  The Domain Verification if (is_null ($oCity [$City])) {return false;}
  Date of birth, if ($BirthYear >2078 | | $BirthYear <1900) {return false;}
  $RealDate = Strtotime ($BirthYear. '-$BirthMonth. '-'. $BirthDay); if (date (' Y ', $RealDate)!= $BirthYear | | date (' m ', $RealDate)!= $BirthMonth | | date (' d ', $RealDate)!= $BirthDay) {return FA
  Lse Return arrAY (' id ' => $id, ' location ' => $oCity [$City], ' Y ' => $BirthYear, ' m ' => $BirthMonth, ' d ' => $BirthDay, ' sex ' =
> $Sex);
 }

16. Gets the collection of a key in a two-dimensional array

$user = Array (0 => array (' ID ' => 1, ' name ' => ' John ', ' email ' => ' zhangsan@sina.com '), 1 => array (' id ' = > 2, ' name ' => ' Dick ', ' email ' => ' lisi@163.com ', 2 => array (' ID ' => 5, ' name ' => ' Harry ', ' email ' => ' 10000@qq.com ',), ...);
$ids = Array (); $ids = Array_map (' Array_shift ', $user);
$ids = Array_column ($user, ' id ');//php5.5
$names = Array (); $names = Array_reduce ($user, Create_function (' $v, $w ', ' $ v[$w ["id"]]= $w ["name"];return $v; ')];

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