thinkphp怎么做模糊查询搜索，完整实例,笨办法

$name = I("post.name");//接收post传值
$mail = I("post.mail");
$age = I("post.age");
if(!empty($name)){
$where["name"] = array("like","%".$name."%");//封装模糊查询 赋值到数组
}
if(!empty($mail)){
$where["mail"] = array("like","%"."$mail"."%");
}
if(!empty($age)){
$where["age"] = $age;
}
//$where["_logic"]="OR";如果查询条件是OR的关系请打开，一般都是AND关系。
$test = M("table")->where($where)->select();

//回传查询条件：age到搜索条件；$this->assign("age",$age);