PHP recursion function return concat string-CodePudding

I have following array

[
  ["client_code","contains","12"],
  "and",
  [
    ["trade_name","=","KeyWholesaler"],
    "or",
    ["trade_name","=","Cash&Carry"]
  ],
  "and",
  [
    "!",
    ["state","=","B-BigCantina"],
    ["state","=","B-BigCantina2"]
  ],
  "and",
  ["client_name","contains","M"]
]

I have made a function that recursively echo above array into MySql where query. I know it is messy but It's best I could do to make it work.

  function testing($array) {
    if(is_array($array) && count($array) == count($array, COUNT_RECURSIVE)) {
      $is_not = $_SESSION["NOT"];
      $and = $_SESSION["NOT"] ? " AND" : "";
      echo "`$array[0]` $is_not$array[1] '$array[2]' $and";
      echo "";
    } else if(is_array($array)) {
      echo "(";
      foreach ($array as $key => $value) {
        testing($value);
      }
      echo ")";
      $_SESSION["NOT"] = "";
    } else if($array == "!") {
      $_SESSION["NOT"] = "!";
    } else {
      echo $array;
      echo "";
    }
  }

The output of following function using given array is as

(`client_code` contains '12' and(`trade_name` = 'KeyWholesaler' or`trade_name` = 'Cash&Carry' )and(`state` != 'B-BigCantina'  AND`state` != 'B-BigCantina2'  AND)and`client_code` contains '21' )

Now this function is just echoing following output but I want to get it into a variable.

Sorry for all formatting and bad english. :)

CodePudding user response：

You can return from within the function and append as string to make a function recursive

  function testing($array) {
    if(is_array($array) && count($array) == count($array, COUNT_RECURSIVE)) {
      $is_not = $_SESSION["NOT"];
      $and = $_SESSION["NOT"] ? " AND" : "";
      return "`$array[0]` $is_not$array[1] '$array[2]' $and";
    } else if(is_array($array)) {
      $val = "";
      foreach ($array as $key => $value) {
        $val =  $val . testing($value);
      }
      $_SESSION["NOT"] = "";
      return "(".$val.")";
    } else if($array == "!") {
      $_SESSION["NOT"] = "!";
    } else {
      return $array;
    }
  }

  echo testing([]);