将Session写入Memcache

<span> 1</span> <?<span>php    
</span><span> 2</span>     <span>class</span><span> MemSession{
</span><span> 3</span>         <span>private</span> <span>static</span> <span>$handler</span> = <span>null</span><span>;
</span><span> 4</span>         <span>private</span> <span>static</span> <span>$lifetime</span> = <span>null</span><span>;
</span><span> 5</span>         <span>private</span> <span>static</span> <span>$time</span> = <span>null</span><span>;
</span><span> 6</span>         <span>const</span> MS = 'session'<span>;
</span><span> 7</span>         
<span> 8</span>         <span>private</span> <span>static</span> <span>function</span> init(<span>$handler</span><span>){
</span><span> 9</span>             self::<span>$handler</span> = <span>$handler</span><span>;
</span><span>10</span>             self::<span>$lifetime</span> = <span>ini_get</span>('session.gc_maxlifetime'<span>);
</span><span>11</span>             self::<span>$time</span> = <span>time</span><span>();
</span><span>12</span> <span>        }
</span><span>13</span>         
<span>14</span>         <span>public</span> <span>static</span> <span>function</span> start(<span>$memcache</span><span>){
</span><span>15</span>             self::init(<span>$memcache</span><span>);
</span><span>16</span>             <span>//</span><span>调用类中的方法要用数组,__CLASS__代表本类</span>
<span>17</span>             <span>session_set_save_handler</span><span>(
</span><span>18</span>                 <span>array</span>(<span>__CLASS__</span>,'open'),
<span>19</span>                 <span>array</span>(<span>__CLASS__</span>,'close'),
<span>20</span>                 <span>array</span>(<span>__CLASS__</span>,'read'),
<span>21</span>                 <span>array</span>(<span>__CLASS__</span>,'write'),
<span>22</span>                 <span>array</span>(<span>__CLASS__</span>,'destroy'),
<span>23</span>                 <span>array</span>(<span>__CLASS__</span>,'gc'<span>)
</span><span>24</span> <span>            );
</span><span>25</span>             <span>session_start</span><span>();
</span><span>26</span> <span>        }
</span><span>27</span>         
<span>28</span>         <span>public</span> <span>static</span> <span>function</span> open(<span>$path</span>,<span>$name</span><span>){
</span><span>29</span>             
<span>30</span> <span>        }
</span><span>31</span>         <span>public</span> <span>static</span> <span>function</span><span> close(){
</span><span>32</span>             
<span>33</span> <span>        }
</span><span>34</span>         
<span>35</span>         <span>public</span> <span>static</span> <span>function</span> read(<span>$PHPSESSID</span><span>){
</span><span>36</span>             <span>$val</span> = self::<span>$handler</span>->get(self::session_key(<span>$PHPSESSID</span><span>));
</span><span>37</span>             
<span>38</span>             <span>if</span>(<span>$val</span>===<span>false</span> || <span>$val</span>==<span>null</span><span>){
</span><span>39</span>                 <span>return</span> <span>false</span><span>;
</span><span>40</span> <span>            }
</span><span>41</span>             <span>return</span> <span>$val</span><span>;
</span><span>42</span> <span>        }
</span><span>43</span>         <span>public</span> <span>static</span> <span>function</span> write(<span>$PHPSESSID</span>,<span>$data</span><span>){
</span><span>44</span>             <span>$method</span> = <span>$data</span>? 'set':'replace'<span>;
</span><span>45</span>             <span>return</span> self::<span>$handler</span>-><span>$method</span>(self::session_key(<span>$PHPSESSID</span>),<span>$data</span>,MEMCACHE_COMPRESSED,self::<span>$lifetime</span><span>);
</span><span>46</span> <span>        }
</span><span>47</span>         
<span>48</span>         <span>public</span> <span>static</span> <span>function</span> destroy(<span>$PHPSESSID</span><span>){
</span><span>49</span>             <span>return</span> self::<span>$handle</span>->delete(self::session_key(<span>$PHPSESSID</span><span>));
</span><span>50</span> <span>        }
</span><span>51</span>         <span>//</span><span>memcache本身就有限定时间，数据自动销毁，所以可不使用gc方法</span>
<span>52</span>         <span>public</span> <span>static</span> <span>function</span> gc(<span>$lifetime</span><span>){
</span><span>53</span>             <span>return</span> <span>true</span><span>;
</span><span>54</span> <span>        }
</span><span>55</span>         
<span>56</span>         <span>//</span><span>给sessionID加前缀，避免key重复</span>
<span>57</span>         <span>private</span> <span>static</span> <span>function</span> session_key(<span>$PHPSESSID</span><span>){
</span><span>58</span>             <span>$session_key</span> = self::MS.<span>$PHPSESSID</span><span>;
</span><span>59</span>             <span>return</span> <span>$session_key</span><span>;
</span><span>60</span> <span>        }        
</span><span>61</span> <span>    }
</span><span>62</span>     <span>$mem</span> = <span>new</span><span> Memcache;
</span><span>63</span>     <span>$mem</span>->connect("localhost",11211) or <span>die</span>("could not connect"<span>);
</span><span>64</span>     MemSession::start(<span>$mem</span>);