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Home php教程 PHP源碼 php常見問題和解決方法二接上

php常見問題和解決方法二接上

Jun 08, 2016 pm 05:33 PM
mysql nbsp quot server

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15:什么是UBB代碼


UBB代碼是HTML的一個變種,是Ultimate?Bulletin?Board?(國外一個BBS程序,國內(nèi)也有不少地方使用這個程序)采用的一種特殊的TAG.
即使禁止使用?HTML,你也可以用?UBBCode??來實現(xiàn).也許你更希望使用?UBBCode??而不是?HTML,?即使論壇允許使用?HTML,?因為使用起來代碼較少也更安全.

Q3boy的UBB里面付有例子,可以直接運行測試


16:我想修改MySQL的用戶,密碼

首先要聲明一點,大部分情況下,修改MySQL是需要有mysql里的root權(quán)限的,?
所以一般用戶無法更改密碼,除非請求管理員.

方法一?
  使用phpmyadmin,這是最簡單的了,修改mysql庫的user表,?
  不過別忘了使用PASSWORD函數(shù)。?

方法二?
  使用mysqladmin,這是前面聲明的一個特例。?
  mysqladmin?-u?root?-p?password?mypasswd?
  輸入這個命令后,需要輸入root的原密碼,然后root的密碼將改為mypasswd。?
  把命令里的root改為你的用戶名,你就可以改你自己的密碼了。?
  當然如果你的mysqladmin連接不上mysql?server,或者你沒有辦法執(zhí)行mysqladmin,?
  那么這種方法就是無效的。?
  而且mysqladmin無法把密碼清空。?

下面的方法都在mysql提示符下使用,且必須有mysql的root權(quán)限:?
  方法三?
  mysql>?INSERT?INTO?mysql.user?(Host,User,Password)?
  VALUES('%','jeffrey',PASSWORD('biscuit'));?
  mysql>?FLUSH?PRIVILEGES?
  確切地說這是在增加一個用戶,用戶名為jeffrey,密碼為biscuit。?
  在《mysql中文參考手冊》里有這個例子,所以我也就寫出來了。?
  注意要使用PASSWORD函數(shù),然后還要使用FLUSH?PRIVILEGES。?

方法四?
  和方法三一樣,只是使用了REPLACE語句?
  mysql>?REPLACE?INTO?mysql.user?(Host,User,Password)?
  VALUES('%','jeffrey',PASSWORD('biscuit'));?
  mysql>?FLUSH?PRIVILEGES?

方法五?
  使用SET?PASSWORD語句,?
  mysql>?SET?PASSWORD?FOR?jeffrey@"%"?=?PASSWORD('biscuit');?
  你也必須使用PASSWORD()函數(shù),?
  但是不需要使用FLUSH?PRIVILEGES。?

方法六?
  使用GRANT?...?IDENTIFIED?BY語句?
  mysql>?GRANT?USAGE?ON?*.*?TO?jeffrey@"%"?IDENTIFIED?BY?'biscuit';?
  這里PASSWORD()函數(shù)是不必要的,也不需要使用FLUSH?PRIVILEGES。?

注意:?PASSWORD()?[不是]以在Unix口令加密的同樣方法施行口令加密。?


17:我想知道他是通過哪個網(wǎng)站連接到本頁



PHP代碼:--------------------------------------------------------------------------------

//必須通過超級連接進入才有輸出
Echo?$_SERVER['HTTP_REFERER'];
?>

--------------------------------------------------------------------------------



18:數(shù)據(jù)放入數(shù)據(jù)庫和取出來顯示在頁面需要注意什么

入庫時
$str=addslashes($str);
$sql="insert?into?`tab`?(`content`)?values('$str')";
出庫時
$str=stripslashes($str);
顯示時
$str=htmlspecialchars(nl2br($str))?;?





19:如何讀取當前地址欄信息



PHP代碼:--------------------------------------------------------------------------------

$s="http://{$_SERVER['HTTP_HOST']}:{$_SERVER["SERVER_PORT"]}{$_SERVER['SCRIPT_NAME']}";?
$se='';?
foreach?($_GET?as?$key?=>?$value)?{?????
$se.=$key."=".$value."&";?????
}???
$se=Preg_Replace("/(.*)&$/","$1",$se);?
$se?$se="?".$se:"";
echo???$s."?$se";?
?>?
--------------------------------------------------------------------------------




20:我點擊后退按鈕,為什么之前填寫的東西不見

這是因為你使用了session.
解決辦法:

PHP代碼:--------------------------------------------------------------------------------

session_cache_limiter('private,?must-revalidate');
session_start();?
...........
..........
?>

--------------------------------------------------------------------------------



21:怎么在圖片里顯示IP地址


PHP代碼:--------------------------------------------------------------------------------


??Header("Content-type:?image/png");
??$img?=?ImageCreate(180,50);
??$ip?=?$_SERVER['REMOTE_ADDR'];
??ImageColorTransparent($img,$bgcolor);
??$bgColor?=?ImageColorAllocate($img,?0x2c,0x6D,0xAF);?//?背景顏色
??$shadow?=?ImageColorAllocate($img,?250,0,0);????//?陰影顏色
??$textColor?=?ImageColorAllocate($img,?oxff,oxff,oxff);???????//?字體顏色
??ImageTTFText($img,10,0,78,30,$shadow,"d:/windows/fonts/Tahoma.ttf",$ip);?//顯示背景
??ImageTTFText($img,10,0,25,28,$textColor,"d:/windows/fonts/Tahoma.ttf","your?ip?is".$ip);?//?顯示IP
??ImagePng($img);
??imagecreatefrompng($img);
??ImageDestroy($img);
?>

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