分享10段PHP常用代码

本文汇集php开发中经常用到的十段代码，包括email、64位编码和解码、解压缩、64位编码、解析json等，希望对您有所帮助。

1、使用php mail函数发送email

$to = "[e-mail]"; 
$subject = "viralpatel.net"; 
$body = "body of your message here you can use html too. e.g. ﹤br﹥ ﹤b﹥ bold ﹤/b﹥"; 
$headers = "from: peter\r\n"; 
$headers .= "reply-to: [e-mail]\r\n"; 
$headers .= "return-path: [e-mail]\r\n"; 
$headers .= "x-mailer: php5\n"; 
$headers .= 'mime-version: 1.0' . "\n"; 
$headers .= 'content-type: text/html; charset=iso-8859-1' . "\r\n"; 
mail($to,$subject,$body,$headers); 
?﹥

2、php中的64位编码和解码

function base64url_encode($plaintext) {
$base64 = base64_encode($plaintext);
$base64url = strtr($base64, '+/=', '-_,');
return $base64url;
}
function base64url_decode($plaintext) {
$base64url = strtr($plaintext, '-_,', '+/=');
$base64 = base64_decode($base64url);
return $base64;
} 

3、获取远程ip地址

function getrealipaddr()
{
if (!empty($_server['http_client_ip'])) //check ip from share internet
{
$ip=$_server['http_client_ip'];
}
elseif (!empty($_server['http_x_forwarded_for'])) //to check ip is pass from proxy
{
$ip=$_server['http_x_forwarded_for'];
}
else
{
$ip=$_server['remote_addr'];
}
return $ip;
}

4、 日期格式化

function checkdateformat($date)
{
//match the format of the date
if (preg_match ("/^([0-9]{4})-([0-9]{2})-([0-9]{2})$/", $date, $parts))
{
//check weather the date is valid of not
if(checkdate($parts[2],$parts[3],$parts[1]))
return true;
else
return false;
}
else
return false;
}

5、验证email

$email = $_post['email'];
if(preg_match("~([a-za-z0-9!#$%&'*+-/=?^_`{|}~])@([a-za-z0-9-]).
   ([a-za-z0-9]{2,4})~",$email)) {
echo 'this is a valid email.';
} else{
echo 'this is an invalid email.';
}

6、在php中轻松解析xml

//this is a sample xml string
$xml_string="﹤?xml version='1.0'?﹥
﹤moleculedb﹥
 ﹤molecule name='benzine'﹥
 ﹤symbol﹥ben﹤/symbol﹥
 ﹤code﹥a﹤/code﹥
 ﹤/molecule﹥
 ﹤molecule name='water'﹥
 ﹤symbol﹥h2o﹤/symbol﹥
 ﹤code﹥k﹤/code﹥
 ﹤/molecule﹥
﹤/moleculedb﹥";
//load the xml string using simplexml function
$xml = simplexml_load_string($xml_string);
//loop through the each node of molecule
foreach ($xml-﹥molecule as $record)
{
 //attribute are accessted by
 echo $record['name'], ' ';
 //node are accessted by -﹥ operator
 echo $record-﹥symbol, ' ';
 echo $record-﹥code, '﹤br /﹥';
}

7、数据库连接

﹤?php
if(basename(__file__) == basename($_server['php_self'])) send_404();
$dbhost = "localhost"; //location of database usually its localhost
$dbuser = "xxxx"; //database user name
$dbpass = "xxxx"; //database password
$dbdatabase = "xxxx"; //database name
$db = mysql_connect("$dbhost", "$dbuser", "$dbpass") or 
   die ("error connecting to database.");
mysql_select_db("$dbdatabase", $db) or die ("couldn't select the database.");
# this function will send an imitation 404 page if the user
# types in this files filename into the address bar.
# only files connecting with in the same directory as this
# file will be able to use it as well.
function send_404()
{
 header('http/1.x 404 not found');
 print '﹤!doctype html public "-//ietf//dtd html 2.0//en"﹥'."n".
 '﹤html﹥﹤head﹥'."n".
 '﹤title﹥404 not found﹤/title﹥'."n".
 '﹤/head﹥﹤body﹥'."n".
 '﹤h1﹥not found﹤/h1﹥'."n".
 '﹤p﹥the requested url '.
 str_replace(strstr($_server['request_uri'], '?'), '', $_server['request_uri']).
 ' was not found on this server.﹤/p﹥'."n".
 '﹤/body﹥﹤/html﹥'."n";
 exit;
}
# in any file you want to connect to the database,
# and in this case we will name this file db.php
# just add this line of php code (without the pound sign):
# include"db.php";
?﹥

8、创建和解析json数据

$json_data = array ('id'=﹥1,'name'=﹥"rolf",'country'=﹥'russia',
"office"=﹥array("google","oracle"));
echo json_encode($json_data);

9、处理mysql时间戳

$query = "select unix_timestamp(date_field) as mydate 
 from mytable where 1=1";
$records = mysql_query($query) or die(mysql_error());
while($row = mysql_fetch_array($records))
{
echo $row;
}

10、解压缩zip文件

﹤?php
 function unzip($location,$newlocation){
 if(exec("unzip $location",$arr)){
 mkdir($newlocation);
 for($i = 1;$i﹤ count($arr);$i++){
 $file = trim(preg_replace("~inflating: ~","",$arr[$i]));
 copy($location.'/'.$file,$newlocation.'/'.$file);
 unlink($location.'/'.$file);
 }
 return true;
 }else{
 return false;
 }
 }
?﹥
//use the code as following:
﹤?php
include 'functions.php';
if(unzip('zipedfiles/test.zip','unziped/mynewzip'))
 echo 'success!';
else
 echo 'error';
?﹥

php常用功能如下

1.php字符串

字符串声明 变量=''或者""（一般情况会使用单引号，因为写起来会比较方便）

$str = 'hello php';
echo $str;

strpos 计算字符在字符串中的位置（从0开始）

$str = 'hello php';
echo strpos($str,'o');  //计算字符在字符串中的位置
echo '<br/>';
echo strpos($str,'ph');

substr 截取字符串

$str = 'hello php';
//截取字符串
$str1 = substr($str,2,3); //从2位置开始截取，截取长度为3的字符串
echo $str1;

不传入长度参数的话，会从指定位置一直截取到字符串的末尾

str_split 分割字符串  固定长度的分割（默认长度为1）

$str = 'hello php';
//分割字符串
$result = str_split($str); //将结果保存到一个数组中
print_r($result); //使用print_r输入一个数组
echo '<br/>';
$result1 = str_split($str,2);
print_r($result1);

explode(分割字符,待分割的字符串) 按照空格进行分割

$str = 'hello php java c# c++';
$result = explode(' ',$str);
print_r($result);

字符串的连接

$str = 'hello php java c# c++';
//字符串的连接
$num = 100;
$str1 = $str.'<br/>objective-c '.$num;
echo $str1;
echo '<br/>';
$str2 = "$str<br/>objective-c $num"; //另一中简便的写法
echo $str2;