11月27日重写数据库操作函数到类-九期线上班

把 php公用方法库中的 数据库操作函数， 重写到 Db类中。

<?php
    namespace Db;
    class Db
    {
        public $dsn;
        public $name;
        public $pass;
        public $pdo;
        public function __construct($dsn,$name,$pass)
        {
            $this->dsn = $dsn;
            $this->name = $name;
            $this->pass = $pass;
            $this->connect();
        }
        public function connect(){
            try {
                $this->pdo = new \PDO($this->dsn, $this->name, $this->pass);
                echo '连接成功<hr>';
            } catch (\PDOException $s){
                die(print_r($s->getMessage(), true));
            }
            return $this->pdo;
        }
        //增加操作
        public function add($table,array $data = [])
        {
            $sql = "INSERT INTO {$table} SET ";
//            print_r($data);
            foreach ($data as $k => $v){
                $sql .= '`' . $k . '`=' . "'$v'" . ',';
            }
            $sql = rtrim(trim($sql),',') . ';';
//            echo $sql;
            //创建数据库预处理对象
            $sqlt = $this->pdo->prepare($sql);
            //执行操作
//            $sqlt->execute();
            if ($sqlt->execute()){
                echo '成功增加' . $sqlt->rowCount() . '条记录！' ;
            }else{
                echo '失败！';
            }
        }
        //更新操作
        public function update($table,$data = [],$where = '')
        {
        $sql = "UPDATE {$table} SET ";
        foreach ($data as $k => $v){
            $sql .= '`' . $k . '`=' . "'$v'" . ',';
        }
        $sql = rtrim(trim($sql),',');
        $sql .= 'WHERE' . $where;
//        echo $sql;
        //创建数据库预处理对象
        $sqlt = $this->pdo->prepare($sql);
        //执行操作
//            $sqlt->execute();
        if ($sqlt->execute()){
            echo '成功修改' . $sqlt->rowCount() . '条记录！' ;
        }else{
            echo '失败！';
        }
        }
        //删除操作
        public function delete($table,$where)
        {
            $sql = "DELETE FROM {$table} WHERE {$where}";
//            echo $sql;
            //创建数据库预处理对象
            $sqlt = $this->pdo->prepare($sql);
            //执行操作
//            $sqlt->execute();
            if ($sqlt->execute()){
                echo '成功删除' . $sqlt->rowCount() . '条记录！' ;
            }else{
                echo '失败！';
            }
        }
        //查询数据
        public function fetch ($table,$fie,$where)
        {
            $sql = "SELECT {$fie} FROM {$table} WHERE {$where};";
////            echo $sql;
//            var_dump($fie);
//            var_dump($table);
//            var_dump($where);
            //创建数据库预处理对象
            $stmt = $this->pdo->prepare($sql);
            $find = $stmt->execute();
            if ($find) {
                return $stmt->fetch(PDO::FETCH_ASSOC);
            } else {
                return false;
            }
        }
    }
    $db = new Db('mysql:host=127.0.0.1;dbname=test1','root','root');
//    $db->add('category',['name'=>'ds','alias'=>'都市生活剧']);
//    $db->update('category',['name'=>'ds','alias'=>'都市生活剧'],'`cate_id`=8');
//    $db->delete('category','`cate_id`=14');
    $db->fetch('category','*','cate_id = 1');
//    echo  $fetch;