如何使用PHP从数据库中获取逗号分隔的值

Question

I have four files named comma separated in one field in database like this file1 , file2 , file3 , file4 . It may change depending on files uploading. User can upload maximum 4 files, minimum one file. But I was not able to get it. I used explode but it's taking too long.

I am using this code:

      $imagefiles = $row["imagefiles"];


      $cutjobs = explode(",", $imagefiles);
      $cutjobs1 = count($cutjobs);

      $image1 = $cutjobs[0];
      $image2 = $cutjobs[1];
      $image3 = $cutjobs[2];
      $image4 = $cutjobs[3];

      if (empty($image1)) {
        $imagefiles1 = "";
      } else {
        $imagefiles1 = 'http://projects.santabantathegreat.com/glassicam/uploads/'.$registerid.
        "/".$viewjobsid.
        "/".$image1;
      }

      if (empty($image2)) {
        $imagefiles2 = "";
      } else {
        $imagefiles2 = 'http://projects.santabantathegreat.com/glassicam/uploads/'.$registerid.
        "/".$viewjobsid.
        "/".$image2;
      }
      if (empty($image3)) {
        $imagefiles3 = "";
      } else {
        $imagefiles3 = 'http://projects.santabantathegreat.com/glassicam/uploads/'.$registerid.
        "/".$viewjobsid.
        "/".$image3;
      }
      if (empty($image4)) {
        $imagefiles4 = "";
      } else {
        $imagefiles4 = 'http://projects.santabantathegreat.com/glassicam/uploads/'.$registerid.
        "/".$viewjobsid.
        "/".$image4;
      }
    }

    $data[] = array( 'imagearray' => array($imagefiles, $imagefiles1, $imagefiles2, $imagefiles3));


  }
  echo json_encode($data);
}  

I am getting output like this :

[{"imagearray":["http:\/\/projects.santabantathegreat.com\/glassicam\/uploads\/60\/30\/file1.jpg","http:\/\/projects.santabantathegreat.com\/glassicam\/uploads\/60\/30\/file2.jpg",""]}]

If you see this imageArray last one is getting "" that means some in file1 , file2 , file3 , file4 one name is missing so I want to show if any filename is not there means I don't want to show null values with ""

i have a field with file1,file2,file3,file4 so times we will have file1,file3 then remaining will not there so i want to count file name separated with commas and if file1 is there is should print that if file3 is there not then it shouldn't show with ""

Answer 1

You could have used split() , but its deprecated in PHP 5.3.0 . So, instead you are left with:

• explode() which is substantially faster because it doesn't split based on a regular expression, so the string doesn't have to be analyzed by the regex parser.

or

• preg_split() which is faster and uses PCRE regular expressions for regex splits.

With preg_split() you could do:

<?php
   $encoded_data = json_encode($data); 
   $images = preg_split('/,/', $encoded_data->imagearray);
?>

I would say that explode() is more appropriate for this.

<?php
   $encoded_data = json_encode($data); 
   $images = explode(',', $encoded_data->imagearray);
   print_r($images);
?>

Resources: What is the difference between split() and explode()?

---

You shouldn't have empty values in your array in the first place. But if you still have any empty values you could use preg_split() something like this one here .

Similarly you can use array_filter() to handle removal of values (null, false,'',0) :

print_r(array_filter($images));

There are so many answers here in this forum that do exactly what you are asking: Remove empty array elements , Delete empty value element in array .