试图计算数组键值包含特定值的次数？

$file = file('file.csv');
$counter=0;
foreach($file as $k){
  if(preg_match('/"/', $k)==1){
    $csv[] = explode(',', $k);
  }
  foreach($k as $key => $value){
    if($value == 'specific value'){
      $counter++;
    }
  }
}
// print_r($csv);
echo $counter;

$k is outputting correctly as an array of comma-separated values; I'm trying to analyze the comma-separated values of each line $k ... getting "Invalid argument supplied for foreach()" error ...

Check, wether $k is an array (is_array($k) and if it is not empty !empty($k) (same as count(arr)>0). Also you should check your CSV-file for errors like blank lines, hidden returns/tabs/etc. .

$file = file('file.csv');
$counter=0;
foreach($file as $k){
  if(preg_match('/"/', $k)==1){
    $csv[] = explode(',', $k);
  }

  if (!is_array($k) OR empty($k)) { continue; }

  foreach($k as $key => $value){
    if($value == 'specific value'){
      $counter++;
    }
  }
}
// print_r($csv);
echo $counter;

Seems to me $k is a string, while $csv is the array you wanna iterate over.