splitting an array at a given line into two parts, inserting another line, and rejoining them

Question

I have an array full of sub arrays. I need to break apart the first array at a given line number, and then insert a new line, and then combine them all back into their original structure.

This is what im working with now

$csvpre = explode("###", $data);

$i = 0;
$bgc = 0;

    foreach ( $csvpre AS $key => $value){
     $info = explode("%%", $value);
     $i++;
     if($i == "1"){
      echo "<tr bgcolor=#efefef><td></td>";
       foreach ( $info as $key => $value ){ echo "<td>$value</td>"; }
      echo "</tr>";

     } else {

      if($bgc&1) { $bgcgo = "bgcolor=\"#b9b9b9\"" ;} else { $bgcgo = "bgcolor=\"#d6d6d6\""; }
      echo "<tr $bgcgo><td></td>";
      echo "<td><input type=button value=\"clone #$i\"></td>";
      $j = 0;
       foreach ( $info as $key => $value ){ 
        $j++;

         if($j != 8){
          echo "<td>$value</td>";
         }else{
          echo "<td><textarea name=ddesc[]>$value</textarea></td>";
         }
       }
      echo "</tr>";
      $bgc++;
     }  
    }

What i need to create, is a function that will take a value for $i, say 10, and at that line split the array into two pieces $arraya and $arrayb. Then i need to combine them back together while including a new line...

pseudo code

$startarray = array(Line0, Line1, Line2, Line3, Line4); $splitline = 2; $arraya = splitup($startarray, $splitline); $arrayb = splitdown($startarray, $splitline);

ArrayA would then consist of Line0, Line1, Line2. And ArrayB would consist of Line3, Line4. Then we run the magic function.

$newline = "Line2.5";
$newarray = somefunction($arraya, $newline, $arrayb);

And $newarray would then look like

Line0, Line1, Line2, Line2.5, Line3, Line4

Answer 1

If I understand your question correctly, array_splice() can do that all in one go:

$array = array('Line0', 'Line1', 'Line2', 'Line3', 'Line4');
array_splice($array, 3, 0, 'Line2.5');
print_r($array);

which outputs:

Array
(
    [0] => Line0
    [1] => Line1
    [2] => Line2
    [3] => Line2.5
    [4] => Line3
    [5] => Line4
)