上傳文件（ID名）

Question

我想通過我的PHP上傳文件，我的代碼是這樣的：

$hasil = mysql_query("select ID from userownfile order by ID DESC"); 
$dt = mysql_fetch_array($hasil); 
$old_id = substr($dt['ID'],2); 

$newId = $old_id[0] + 1; 

$base = $_REQUEST['image']; 
$filename = $newId . ".jpg"; 
$buffer = base64_decode($base); 
$path = "img/" . $filename . ".jpg"; 
$handle = fopen($path, 'wb'); 
$numbytes = fwrite($handle, $buffer); 
fclose($handle); 
$conn = mysql_connect("localhost","root",""); 
mysql_select_db("db_bloodglucose"); 
$sql = "insert into userownfile(ID, file) values('" . $newId . "','" . $path . "')"; 
$r = mysql_query($sql); 

在第一次上傳，我已經贏得成功上傳的文件哪個名稱1 .jpg，但是當我想上傳第二次等，它沒有顯示在我的數據庫上，它不斷顯示1.jpg，我想知道爲什麼數字沒有增加..任何人都可以幫助我？謝謝，我已經

之前更改我的代碼是這樣的：

<?php 

$hasil = mysql_query("select ID from userownfile order by ID DESC"); 
$dt = mysql_fetch_array($hasil); 
$old_id = substr($dt['ID'],2); 

$newId = mysql_insert_id() + 1; 

$base = $_REQUEST['image']; 
$filename = $newId . ".jpg"; 
$buffer=base64_decode($base); 
$path = "img/".$filename.".jpg"; 
$handle = fopen($path, 'wb'); 
$numbytes = fwrite($handle, $buffer); 
fclose($handle); 
$conn=mysql_connect("localhost","root",""); 
mysql_select_db("db_bloodglucose"); 
$sql = "insert into userownfile(ID, file) values('" . $newId . "','" . 

$path . "')"; 
$r=mysql_query($sql); 
?> 

但是，它保持貼着1，數量不增加，任何人都可以幫我嗎？

Answer 1

我猜的錯誤是在這裏：

$dt = mysql_fetch_array($hasil) 
$old_id = substr($dt['ID'],2); 
$newId = $old_id[0]+1; 

可能

$newId = $dt[0]+1; 

或只是

$newId = $old_id+1; 

但更好地利用mysql_insert_id，這將給你插入的記錄ID到避免併發問題。