//参数1是类名,参数2是方法名
$func = new ReflectionMethod('UnifiedOrder_pub', 'getPrepayId');
//从第几行开始
$start = $func->getStartLine() - 1;
//从第几行结束
$end =  $func->getEndLine() - 1;
//获取路径地址
$filename = $func->getFileName();

//这是通过方法名查找方法所在位置

 $funcName="SafeHtml"; //要查找的函数名
 Reflection::export(new ReflectionFunction($funcName));

//查找类名所在位置
$func = new ReflectionClass('counter');  
echo    $func->getFileName();  

<?php
//摘自：http://www.dewen.org/q/10775
function a() {
}

class b {
    public function f() {
    }
}

function function_dump($funcname) {
    try {
        if(is_array($funcname)) {
            $func = new ReflectionMethod($funcname[0], $funcname[1]);
            $funcname = $funcname[1];
        } else {
            //这个应该是当只有一个参数的时候就看做是本类的发放吧,大概,自行百度
            $func = new ReflectionFunction($funcname);
        }
    } catch (ReflectionException $e) {
        echo $e->getMessage();
        return;
    }
    $start = $func->getStartLine() - 1;
    $end =  $func->getEndLine() - 1;
    $filename = $func->getFileName();
    echo "function $funcname defined by $filename($start - $end)\n";
}
function_dump('a');
function_dump(array('b', 'f'));
$b = new b();
function_dump(array($b, 'f'));
?>