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php将图片保存入mysql数据库失败的解决方法_php技巧

May 16, 2016 pm 08:27 PM
mysql php keep picture fail database Solution

本文实例分析了php将图片保存入mysql数据库失败的解决方法。分享给大家供大家参考。具体分析如下:

图片保存数据库并不是一个明智的做法,我们多半是把图片保存到服务器,然后把图片地址保存到数据库,这样我们每次只要读出图片地址就可以显示了,但下面我还是来介绍一个图片保存到mysql数据库的问题解决办法,代码如下:

复制代码 代码如下:
require 'class/db.php';
$fileName = "a1.jpg";
$fp = fopen($fileName, "r");
$img = fread($fp, filesize($fileName));
fclose($fp);
 
$db->execute("insert db2.testimg (`img`) values ('$img') ;");

报错:

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '`?绶q?仳!????1丶>,Mo?'^WZ4in??T春??????U?楹?' at line 1

代码如下:

复制代码 代码如下:
$img = fread($fp, filesize($fileName));
$img = addslashes($img)

继续报错,各种搜索,百度里的结果都是addslashes,要不就是addslashes也没有的,真是扯淡啊.

复制代码 代码如下:
base64_decode
$img = base64_encode($img);

插入成功,图片文件17.0k,出来进行base64_decode,显示正常,找到个16进制的办法:

复制代码 代码如下:
$img = bin2hex($img);

有效,输出不用解密,存入数据库很大 25K,比base64还坑爹呢,再找,后来,后来,发现phpmyadmin直接上传的图片文件可以用文件比base64的小,文件12.8k.

翻phpmyadmin 源代码,common.lib.php文件183有个神奇的函数,代码如下:

复制代码 代码如下:
function PMA_sqlAddslashes($a_string = '', $is_like = false, $crlf = false, $php_code = false)
{
    if ($is_like) {
        $a_string = str_replace('\', '\\\\', $a_string);
    } else {
        $a_string = str_replace('\', '\\', $a_string);
    }
 
    if ($crlf) {
        $a_string = str_replace("n", 'n', $a_string);
        $a_string = str_replace("r", 'r', $a_string);
        $a_string = str_replace("t", 't', $a_string);
    }
 
    if ($php_code) {
        $a_string = str_replace(''', '\'', $a_string);
    } else {
        $a_string = str_replace(''', '''', $a_string);
    }
 
    return $a_string;
} // end of the 'PMA_sqlAddslashes()' function$img = PMA_sqlAddslashes($img);

文件大小12.8K 和phpmyadmin的一样大.

例,前台image.html,代码如下:

复制代码 代码如下:


  上传图片

 


 
 File:
 



后台处理upimage.php代码如下:
复制代码 代码如下:
 //向数据库中插入图片
 $imgfile=$_FILES['imgfile'];
 $submitbtn=$_POST['submitbtn'];
 if($submitbtn=='OK' and is_array($imgfile)){
 $name=$imgfile['name'];  //取得图片名称
 $type=$imgfile['type']; //取得图片类型
 $size=$imgfile['size'];  //取得图片长度
 $tmpfile=$imgfile['tmp_name'];  //图片上传上来到临时文件的路径
 if($tmpfile and is_uploaded_file($tmpfile)){  //判断上传文件是否为空,文件是不是上传的文件
  //读取图片流
  $file=fopen($tmpfile,"rb");
  $imgdata=bin2hex(fread($file,$size));  //bin2hex()将二进制数据转换成十六进制表示
  fclose($file);
 
  $mysqli=mysql_connect("localhost","root","123456″);  //连接数据库函数
  mysql_select_db("test");  //选择数据库
  //插入出数据库语句,图片数据前要加上0x,用于表示16进制数
  if(mysql_query("insert into images(name,type,image) values('".$name."','".$type."',0x".$imgdata.")"))
   echo "
插入成功!

显示图片
";
  else
   echo "
插入失败!
";
  mysql_close();
 }else
 echo "
请先选择图片!

点此返回
";
} else
 echo "
请先选择图片!

点此返回
";
?>

显示图片disimage.php,代码如下:
复制代码 代码如下:
 mysql_connect("localhost","root","123456″);
 mysql_select_db("test");
 //显示最新插入的那张图片
 $result=mysql_query("select image from images where id=(select max(id) from images)");
 $row=mysql_fetch_object($result);
 header("Content-Type:image/pjpeg");
 echo $row->image;
 mysql_close();
?>

结论:

PMA_sqlAddslashes好用 文件12.8k 和原来图片一样大

bin2hex 16进制 好用文件25K

base64_encode 好用,出来的文件需要base64_decode 17K

addslashes 不好用,继续报错,注明,在某些windows机器上addslashes好用.

希望本文所述对大家的php程序设计有所帮助。

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