$User->where('id=5')->setDec('score',5);

D:\LearnWebDevelop\php\thinkphp_3.2.3_full\Application\Home\Controller\UserController.class.php

<?php
namespace Home\Controller;
use Think\Controller;
class UserController extends Controller{
           //下面是一个标准的URL访问格式：
           //http://serverName/index.php/模块/控制器/操作(/参数名/参数值)
//http://localhost/thinkphp323/index.php/home/Form/add
//http://localhost/thinkphp323/index.php/home/index/hello/name/baby



    //http://localhost/thinkphp323/index.php/home/User/inc_score?id=1&value=1
    public function inc_score($id=1,$value=1){
        $User = M("User"); // 实例化User对象
        $User->where('id=' . $id)->setInc('score',(int)$value); // 用户的积分加
    }

    //http://localhost/thinkphp323/index.php/home/User/dec_score?id=1&value=1
    public function dec_score($id=1,$value=1){
        $User = M("User"); // 实例化User对象
        $User->where('id=' . $id)->setDec('score',(int)$value); // 用户的积分加
    }

//$User = M("User"); // 实例化User对象
//$User->where('id=5')->setInc('score',3); // 用户的积分加3
//$User->where('id=5')->setInc('score'); // 用户的积分加1
//$User->where('id=5')->setDec('score',5); // 用户的积分减5
//$User->where('id=5')->setDec('score'); // 用户的积分减1


}

CREATE TABLE IF NOT EXISTS `think_user` (
`id` smallint(4) unsigned NOT NULL AUTO_INCREMENT,
`username`  varchar(255) NOT NULL,
`score` INTEGER  NOT NULL,
`create_time` int(11) unsigned NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 ;