PHP文件路径命名问题

I tried creating a script to upload multiple photos, rename photo, and add database entry. The database filename entry is correct however the image upload filename is compounding the jpg name.

ie. Database entry is correctly naming files: photo_1, photo_2, photo_3

The files are being uploaded named incorrectly: photo_1.jpg, photo_1.jpgphoto_2.jpg, photo_1.jpgphoto_2.jpgphoto_3.jpg

Not sure how to resolve this as my database entry is correct.

    <?php
if (isset($_POST['submit'])) {
    $j = 0; //Variable for indexing uploaded image 
    $image_post_id = $_POST["image_post_id"];

    $target_path = "uploads/"; //Declaring Path for uploaded images
    for ($i = 0; $i < count($_FILES['file']['name']); $i++) {//loop to get individual element from the array




        $validextensions = array("jpeg", "jpg", "png", "JPG", "PNG", "JPEG");  //Extensions which are allowed
        $ext = explode('.', basename($_FILES['file']['name'][$i]));//explode file name from dot(.) 

        $file_extension = end($ext); //store extensions in the variable





        //MYSQL Handling

            mysql_query( "INSERT INTO post_images(`image_filename`, `image_post_id`) VALUES('0', '".addslashes($image_post_id)."')" );
                            $new_id = mysql_insert_id();

                            $target_path = $target_path . "post_". $new_id . "." . strtolower($ext[count($ext) - 1]);//set the target path with a new name of image
                            mysql_query( "UPDATE post_images SET image_filename='post_".addslashes($new_id).".".strtolower($ext[count($ext) - 1])."' WHERE image_id='".addslashes($new_id)."'" );












        $j = $j + 1;//increment the number of uploaded images according to the files in array       

      if (($_FILES["file"]["size"][$i] < 1000000) //Approx. 100kb files can be uploaded.
                && in_array($file_extension, $validextensions)) {
            if (move_uploaded_file($_FILES['file']['tmp_name'][$i], $target_path)) {//if file moved to uploads folder
                echo $j. ').<span id="noerror">Image uploaded successfully!.</span><br/><br/>';
            } else {//if file was not moved.
                echo $j. ').<span id="error">please try again!.</span><br/><br/>';
            }
        } else {//if file size and file type was incorrect.
            echo $j. ').<span id="error">***Invalid file Size or Type***</span><br/><br/>';
        }
    }
}
?>

Your problem is with this line in your for loop:

$target_path = $target_path . "post_". $new_id . "." . strtolower($ext[count($ext) - 1]);

This code essentially says "Append the new filename to the previous value", which obviously is not what you want.

To fix, just remove the $target_path on the right of the =:

$target_path = "post_". $new_id . "." . strtolower($ext[count($ext) - 1]);