yii2使用ActiveRecord類對數據庫的操作

ActiveRecord提供了一套面向對象的對數據庫進行增刪改查的方法，很實用，省去了select*的一系列操作

注意:一個ActiveRecord類對應一個數據表

首先來創建一個model，然後model內如下配置

<?php

namespace frontend\models;

use yii\db\ActiveRecord;

class Userinfo extends ActiveRecord
{
    //這裏來配置連接的表名
	public static function tableName()
    {
        return 'userinfo';
    }
}

下面就可以開始對username表進行操作了

1.find()方法的使用

//獲取表中所有數據信息並數組化
	public static function getallusermsg()
	{
        $model = self::find() -> asArray()  -> all();
		return $model;
	}
//按條件查詢
    public static function getusermsg($username)
	{
        $model = self::find() -> asArray() -> where(['username' => $username]) -> one();
		return model;
	}
//數據庫添加
    public static function setusermsg($userinfo)
    {
    	$userinfotable = new userinfo;
    	$userinfotable->username = $userinfo['username'];
    	$userinfotable->password = $userinfo['password'];
    	$userinfotable->role = $userinfo['role'];
    	if ($userinfotable->save()) {
    		return ['code' => 200,'message' => '註冊成功！'];
    	} else {
    		return ['code' => 201,'message' => '註冊失敗！'];
    	}
    }
//數據庫更新
    public static function setusermsg($username)
    {
    	$model = self::find() -> asArray() -> where(['username' => $username]) -> one();
        $model->username = 'suibian';
    	if ($model->save()) {
    		return ['code' => 200,'message' => '註冊成功！'];
    	} else {
    		return ['code' => 201,'message' => '註冊失敗！'];
    	}
    }
//數據庫刪除
    public static function setusermsg($username,$password)
    {
    	$model = self::find() -> asArray() -> where(['username' => $username,'password' => $password]) -> one();
    	if ($model->delete()) {
    		return ['code' => 200,'message' => '註冊成功！'];
    	} else {
    		return ['code' => 201,'message' => '註冊失敗！'];
    	}
    }

注：self爲改類，asArray()是將所查數據數組化

2.ActiveRecord類常用的方法

all()/one() -----返回一條還是所有

orderBy()/andOrderBy() ----- 對數據進行排序

count() -----返回查詢條件下的數據條數

with() -----指定關聯表的字段

where()/andWhere()/orWhere() ---- 條件查詢