Simple PHP anti-injection content filtering method_PHP tutorial

Content filtering is mainly to prevent some security injections or cross-domain operations. Let’s take a look at some simple anti-injection content filtering program codes that I compiled. I hope the article will be helpful to all students.

Method 1, filter some useless content

The filtering of useless information is strict, and useful information may not be entered. You can find other filtering methods on the Internet:

Example 2 Filter some html tags

The code is as follows

代码如下	复制代码
function checkHtml($data){   $ret  = preg_match("/['.,:;*?~`!@#$%^&+=)({}]|]|[|/||"||/",$data);   if ($ret == 1) {     return false; exit;   } else {     return true;   } }

Copy code

代码如下	复制代码
function uh($str) { $farr = array( "/s+/", //过滤多余的空白 "/]*?)>/isU", //过滤 <script></script> "/(]*)on[a-zA-Z]+s*=([^>]*>)/isU", //过滤javascript的on事件 ); $tarr = array( " ", "＜123＞", //如果要直接清除不安全的标签，这里可以留空 "12", ); $str = preg_replace( $farr,$tarr,$str); return $str; }

function checkHtml($data){
$ret = preg_match("/['.,:;*?~`!@#$%^&+=)({}]|]|[|/||"||/",$ data);
if ($ret == 1) {
Return false; exit;
} else {
Return true;
}
}

代码如下

复制代码

if($_POST) {  //获取文件内容转为数组两种方法：  /*  $fcon = file_get_contents("./filter.txt");  $filter_word = explode("n",$fcon);  */  $filter_word = file("./filter.txt");  //$filter_word = array("test1","test2","test3","test4");  $str = $_POST["mess"];  for($i=0;$i  {   if(preg_match("/".(trim($filter_word[$i]))."/i",$str))   {    echo "<script>alert('您输入的内容含非法内容，请重输！');</script>";    echo "返回";    exit;   }  }  echo "您输入的内容是:".$str; } ?> 测试过滤是否生效:

The code is as follows

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function uh($str)
{
$farr = array(
"/s+/", //Filter excess whitespace
"/]*?)>/isU", //Filter "/(]*)on[a-zA-Z]+s*=([^>]*>)/isU", //Filter the on event of javascript
);
$tarr = array(
" ",
"＜123＞", //If you want to directly clear unsafe tags, you can leave it blank here
"12",
);
$str = preg_replace( $farr,$tarr,$str);
return $str;
} Method three, the above two methods both put the content to be filtered in the program. Next, I put the content to be filtered into a txt text. The second time, I only need to read the file content to make a judgment, which is convenient for maintenance. Content to filter.

The code is as follows

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if($_POST) { //Two ways to get the file content and convert it into an array: /* $fcon = file_get_contents("./filter.txt"); $filter_word = explode("n",$fcon); */ $filter_word = file("./filter.txt"); //$filter_word = array("test1","test2","test3","test4"); $str = $_POST["mess"]; for($i=0;$i { if(preg_match("/".(trim($filter_word[$i]))."/i",$str)) { echo "<script>alert('The content you entered contains illegal content, please re-enter!');</script>"; echo "return"; exit; } } echo "The content you entered is:".$str; } ?> Test whether filtering is effective: http://www.bkjia.com/PHPjc/632820.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/632820.htmlTechArticleContent filtering is mostly to prevent some security injections or cross-domain operations. Let’s take a look at what I have compiled A few simple anti-injection content filtering program codes, I hope the article will be helpful to everyone...