php函数ob_start()、ob_end_clean()、ob_get_contents()

Example #1 A simple ob_get_contents() example
<?php

ob_start();

echo "Hello ";

$out1 = ob_get_contents();

echo "World";

$out2 = ob_get_contents();

ob_end_clean();

var_dump($out1, $out2);
?>

以上例程会输出：

string(6) "Hello "
string(11) "Hello World"

Example #1 ob_end_clean() example
<?php
ob_start();
echo 'Text that won't get displayed.';
ob_end_clean();
?>

<?php
//实例：计算页面运行时加载时间
//分析：页面打开时获取一个时间，加载完成时获取一个时间，运行时间即二者之差

//1.自定义函数
function fn(){
 list($a,$b) = explode(' ',microtime()); //获取并分割当前时间戳和微妙数，赋值给变量
 return $a+$b;
}

//2.获取开始时间
$start_time = fn();
//5.加载过程
for($i=0;$i<10000000;$i++){
 // do nothing;
}

//3.获取结束时间
$end_time = fn();

//4.计算差值
echo $end_time-$start_time;

//5.格式化输出
echo '<br />';
$t = $end_time-$start_time;
echo round($t,2);

?>

<?php
class runtime
{
        var $StartTime = 0;
        var $StopTime = 0;
        function get_microtime()
        {
                list($usec, $sec) = explode(' ', microtime());
                return ((float)$usec (float)$sec);
        }
       
        function start()
        {
                $this->StartTime = $this->get_microtime();
        }
       
        function stop()
        {
                $this->StopTime = $this->get_microtime();
        }
       
        function spent()
        {
                return round(($this->StopTime - $this->StartTime) * 1000, 1);
        }
}

//实例开始
$runtime= new runtime;
$runtime->start();
//你的代码开始
$a = 0;
for($i=0; $i<1000000; $i )
{
        $a = $i;
}
//你的代码结束
$runtime->stop();
echo "页面执行时间: ".$runtime->spent()." 毫秒";
?>

{ "_id" : ObjectId("504eea97e4b023cf38e34039"), "in_ts" : NumberLong("1347349143699"), "log" : { "guid" : "4D1F3079-7507-F4B0-E7AF-5432D5D8229D", "p" : "View_Prop_YepPage_Zheng", "cid" : "11", "url" : "http://shanghai.haozu.com/rental/broker/n/10481780", "rfpn" : "Listing_V2_IndexPage_All", "site" : "haozu", "agent" : "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)", "stamp" : "1347349162159", "cip" : "116.226.70.44", "referer" : "http://shanghai.haozu.com/shop/1464934/", "cstamp" : "1347349323125", "sessid" : "FA798056-F9E7-F961-41E0-CC95C850FA47", "uguid" : "C00FF55B-3D3D-4B31-4318-12345B0DBE64", "pn" : "View_Prop_YepPage_Zheng", "cstparam" : { "proId" : NumberLong(10481780), "brokerId" : "326792", "tradeType" : "2", "userType" : "0", "channel" : "site", "entry" : "1", "COMMID" : "1666" } }, "out_ts" : NumberLong("1347349466083"), "rule" : 0, "status" : "ok", "txid" : 0 }

{ "_id" : ObjectId("504eea97e4b023cf38e34039"), "in_ts" : NumberLong("1347349143699"), "log" : { "guid" : "4D1F3079-7507-F4B0-E7AF-5432D5D8229D", "p" : "View_Prop_YepPage_Zheng", "cid" : "11", "url" : "http://shanghai.haozu.com/rental/broker/n/10481780", "rfpn" : "Listing_V2_IndexPage_All", "site" : "haozu", "agent" : "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)", "stamp" : NumberLong("1347349162159"), "cip" : "116.226.70.44", "referer" : "http://shanghai.haozu.com/shop/1464934/", "cstamp" : "1347349323125", "sessid" : "FA798056-F9E7-F961-41E0-CC95C850FA47", "uguid" : "C00FF55B-3D3D-4B31-4318-12345B0DBE64", "pn" : "View_Prop_YepPage_Zheng", "cstparam" : { "proId" : NumberLong(10481780), "brokerId" : "326792", "tradeType" : "2", "userType" : "0", "channel" : "site", "entry" : "1", "COMMID" : "1666" } }, "out_ts" : NumberLong("1347349466083"), "rule" : 0, "status" : "ok", "txid" : 0 }为字符串时，使用下面的查询是正常的

        $query = array ('log.stamp' => array ('$gte' => ‘1347346800000’, '$lt' => ‘1347350400000’));

        $query = array ('log.stamp' => array ('$gte' => new MongoInt64($time_range['start']), '$lt' => new MongoInt64($time_range['end'])));

<?php
　　　　权限修饰符 class 类名{   //权限修士符号:public,protected,private 或者省略3者.
　　　　　　//类体;　　　　　　　　//class 是建类关键字
　　　　}　　　　　　　　　　　　　//类名必须跟在class 后面,且跟上{}.{}之间放类的成员.
　　?>
//ps:在class关键字前可以加权限修饰符外,还可以加static,abstract等关键字.一个类,即一对大括号之间的全部内容都要在一段代码段中,不允许将类中的内容分割成对块.
<?php
　　class ConnDB{
　　　　//....
?>
<?

　　　　//...
　　};
?>

function _get($str){
$val = !empty($_GET[$str]) ? $_GET[$str] : null;
return $val;
}

error_reporting(E_ALL ^ E_NOTICE);

$var = isset($_GET['a'])?$_GET['a']:'';