$cache = new Cache();

$cache = new Cache(60, '/any_other_path/');

$value = $cache->get('data_key');

$value = $cache->put('data_key', 'data_value');

$cache = new Cache();

//从缓存从读取键值 $key 的数据
$values = $cache->get($key);

//如果没有缓存数据
if ($values == false) {
	//insert code here...
	//写入键值 $key 的数据
	$cache->put($key, $values);
} else {
	//insert code here...
}

<?php
/**
*  简单实用的php缓存类
*  Edit: www.
*/
class Cache {
	private $cache_path;//path for the cache
	private $cache_expire;//seconds that the cache expires

	//cache constructor, optional expiring time and cache path
	public function Cache($exp_time=3600,$path="cache/"){
		$this->cache_expire=$exp_time;
		$this->cache_path=$path;
	}

	//returns the filename for the cache
	private function fileName($key){
		return $this->cache_path.md5($key);
	}

	//creates new cache files with the given data, $key== name of the cache, data the info/values to store
	public function put($key, $data){
		$values = serialize($data);
		$filename = $this->fileName($key);
		$file = fopen($filename, 'w');
	    if ($file){//able to create the file
	        fwrite($file, $values);
	        fclose($file);
	    }
	    else return false;
	}

	//returns cache for the given key
	public function get($key){
		$filename = $this->fileName($key);
		if (!file_exists($filename) || !is_readable($filename)){//can't read the cache
			return false;
		}
		if ( time() < (filemtime($filename) + $this->cache_expire) ) {//cache for the key not expired
			$file = fopen($filename, "r");// read data file
	        if ($file){//able to open the file
	            $data = fread($file, filesize($filename));
	            fclose($file);
	            return unserialize($data);//return the values
	        }
	        else return false;
		}
		else return false;//was expired you need to create new
 	}
}
?>

分享一个php上传单个文件到ftp服务器的简单例子。

代码：

<?php
/**
* php 文件上传简单范例
* by www.
*/
// FTP连接参数
$host = 'ftp.xxx.com';
$usr = 'user';
$pwd = 'password';
  
// 用于上传的文件:
$local_file = './example.txt';
$ftp_path = '/data/example.txt';
  
// 连接ftp
$conn_id = ftp_connect($host, 21) or die ("Cannot connect to host");
  
// 发送连接参数
ftp_login($conn_id, $usr, $pwd) or die("Cannot login");
  
// turn on passive mode transfers (some servers need this)
// ftp_pasv ($conn_id, true);
  
// perform file upload
$upload = ftp_put($conn_id, $ftp_path, $local_file, FTP_ASCII);
  
// 检测上传状态:
print (!$upload) ? 'Cannot upload' : 'Upload complete';
print "\n";
  
/*
** Chmod the file (just as example)
*/
  
// If you are using PHP4 then you need to use this code:
// (because the "ftp_chmod" command is just available in PHP5+)
if (!function_exists('ftp_chmod')) {
   function ftp_chmod($ftp_stream, $mode, $filename){
        return ftp_site($ftp_stream, sprintf('CHMOD %o %s', $mode, $filename));
   }
}
  
// try to chmod the new file to 666 (writeable)
if (ftp_chmod($conn_id, 0666, $ftp_path) !== false) {
    print $ftp_path . " chmoded successfully to 666\n";
} else {
    print "could not chmod $file\n";
}
  
// close the FTP stream
ftp_close($conn_id);
?>

在Linux中安装PHP的GD支持库，步骤如下：
一、下载
 

二、安装

1.安装zlib
 

2.安装libpng
 

注意，这里的makefile不是用./configure生成，而是直接从scripts/里拷一个

3.安装freetype
 

4.安装Jpeg
 

注意，这里configure一定要带--enable-shared参数，不然，不会生成共享库

5.安装GD
 

上面的安装步骤是没有设定 安装目录的，测试重新编译PHP时用上面方法均可。
若要指定安装地址，请采用如下方式，推荐定义安装目录。
 
1、安装 zlib
 

2、安装 jpeg
 

安装完成提示：
Libraries have been installed in:
/usr/local/jpeg6/lib
 
3、安装 libpng
 

4、安装 freetype
 

5、安装 GD
 

安装jpg时，如果出错，需要先装libtool：
libtool-1.X.tar.gz  //是我下载的版本
 

不然如果其他的需要这个包还得指它的路径
 
这里可能会出错
checking host system type… Invalid configuration `x86_64-unknown-linux-gnu ‘: machine `x86_64-unknown ‘ not recognized
checking build system type… Invalid configuration `x86_64-unknown-linux-gnu ‘: machine `x86_64-unknown ‘ not recognized
configure: error: libtool configure failed 
 
或者
/libtool --mode=compile gcc -O2  -I. -c ./jcapimin.c
make: ./libtool：命令未找到
make: *** [jcapimin.lo] 错误 127
./libtool --mode=compile gcc -O2  -I. -c ./cjpeg.c
make: ./libtool：命令未找到
make: *** [cjpeg.lo] 错误 127 
 
解决方法
cp /usr/share/libtool/config/config.guess .
cp /usr/share/libtool/config/config.sub .
cp到jpeg的安装文件目录，注意后面的个“.”
make clean
 
再重新
./configure --prefix=/usr/local/libjpeg/   --enable-shared  --enable-static
make
make install
--------------------------------
如果已经安装php，建议通过追加编译安装
进入“[php解压目录]/ext/gd”目录，执行如下命令：
[php安装目录]/bin/phpize
./configure --with-php-config=[php安装目录]/bin/php-config --with-jpeg=[jpeg-6b安装目录] --with-png=[libpng安装目录] --with-freetype=[freetype安装目录] --with-gettext=[gettext安装目录] --with-gd=[gd安装目录] 
make 
make install 
 
安装成功后会在“[php安装目录]/lib/php/extensions/no-debug-non-zts-20060613”目录下生成gd.so文件，
然后cp [php安装目录]/lib/php/extensions/no-debug-non-zts-20060613/gd.so /opt/php/ext
 
修改php.ini文件加载gd组件，添加extension_dir=/opt/php/ext和extension=gd.so，如果有extension_dir=/opt/php/ext则不需要增加
extension_dir=/opt/php/ext 
extension=gd.so