PHP中一些可以替代正则表达式函数的字符串操作函数

0x01:根据预定义的字符对字符串进行词法分析

复制代码 代码如下:
<"lv chen yang|Hello:world&757104454@qq.com";
//定义界定符，包括(|)(:)( )(&)
$tokens="|:& ";
$tokened=strtok($info, $tokens);
while ($tokened)
{
 echo "Element:$tokened<br/>";
 //连续调用strtok()函数，完成对整个字符串的词法分析
 $tokened=strtok($tokens);
}
"codetitle">复制代码 代码如下:
<"
   In the latest installment of the ongoing Developer.com PHP series.
   I discuss the many improvements and addtions to
   <a href=\"http:www.php.com\">PHP</a> object-oriented architecture.
   ";
echo "<br/>";
$words=explode(' ', strip_tags($summary));
echo "This sentence's lenght is:".sizeof($words);
/*
 * explode()函数始终比preg_split、spilt()和spliti()快得多。因此，在不需要使用正则表达式时，一定要使用这个函数。
 */
"codetitle">复制代码 代码如下:
<"Chengdu","Chongqing","Beijing","Shanghai","Guangzhou");
$citystring=implode("|", $citys);
echo $citystring;
"codetitle">复制代码 代码如下:
<"index.html";
$log=<<<logfile
192.168.1.1:/www/htdocs/index.html:[2013/06/26:13:25:10]
192.168.1.2:/www/htdocs/index.html:[2013/06/26:13:27:16]
192.168.1.3:/www/htdocs/index.html:[2013/06/26:13:28:45]
logfile;
echo "<br/>";
//$substr在log中首次出现的位置是什么
$pos=strpos($log, $substr);
//查找行结束的数值位置
$pos1=strpos($log,"\n",$pos);
//计算时间戳的开始
$pos=$pos+strlen($substr)+1;
//检索时间戳
$timestamp=substr($log, $pos,$pos1-$pos);
echo "The file index.html was first accessed on: $timestamp<br/>";
/*
 * 函数stripos()和函数strpos()函数用法相同，唯一的区别是stripos()不区分大小写。
 */
"codetitle">复制代码 代码如下:
<"In the latest installment of the ongoing Developer.com PHP series.
   I discuss the many improvements and addtions to
   <a href=\"http:www.php.com\">PHP</a> object-oriented architecture. ";
if(strlen($summary)>$limit)
 $summary=substr($summary, 0,strrpos(substr($summary, 0,$limit)," "))."...";
echo  $summary;
"codetitle">复制代码 代码如下:
<"lvchenyang@live.cn";
$email=str_replace("@", "(at)", $email);
echo "<br/>".$email;
"codetitle">复制代码 代码如下:
<"lvchenyang@live.cn";
echo "<br/>".ltrim(strstr($url, "@"),"@");
"codetitle">复制代码 代码如下:
<"lvchenyang";
echo "<br/>".substr($str, 2,4);
//output: chen
"codetitle">复制代码 代码如下:
<"<br/>";
$sentencearray=explode(" ", $talk);
foreach ($sentencearray as $item)
{
 echo "The word <strong>$item</strong> appears(".substr_count($talk, $item).")times<br/>";
}
"codetitle">复制代码 代码如下:
<"15926841384";
echo "<br/>".substr_replace($phonenum, "****", 3,4);
?>