orm使用

待我称王封你为后i 2022-04-15 23:51 175阅读 0赞

用户结构体，和订单是一对多的关系

type User struct {
    	Id int //beego中默认Id为主键，且自增长
    	Name string //姓名
    	Age int //年龄
    	Nickname string  //昵称
    	Userorders []*Userorder `orm:"reverse(many)"`
    }

订单结构体，和用户是多对多一的关系

type Userorder struct {
    	Id int
    	Orderdata string
    	User *User `orm:"rel(fk)"`
    	Products []*Product `orm:"rel(m2m)"`//ManyToMany
    }

创建orm对象，插入用户：

func (this *InsertUserController) Get() {
    	this.TplName = "insertuser.html"
    }
    func (this *InsertUserController) Post() {
    	name := this.GetString("name")
    	age, err := this.GetInt("age")
    	if err != nil {
    		this.Ctx.WriteString("插入失败!")
    	}
    	nickname := this.GetString("nickname")
    	user := models.User{Name:name, Age:age, Nickname:nickname}
    	orm := orm.NewOrm()
    	//INSERT INTO USER (NAME, age, nickname)  VALUE('Alice', 24, 'bb')
    	n, err := orm.Insert(&user)
    	if err == nil && n > 0 {
    		this.Ctx.WriteString("插入成功!")
    	}else {
    		this.Ctx.WriteString("插入失败!")
    	}
    }

insertuser.html

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>插入用户</title>
    </head>
    <body>
        <form action="/insertuser" method="post">
            <table>
                <thead>插入用户</thead>
                <tbody>
                    <tr>
                        <td>姓名:</td>
                        <td>
                            <input id="name" name="name" type="text">
                        </td>
                    </tr>
                    <tr>
                        <td>年龄:</td>
                        <td>
                            <input id="age" name="age" type="text">
                        </td>
                    </tr>
                    <tr>
                        <td>昵称:</td>
                        <td>
                            <input id="nickname" name="nickname" type="text">
                        </td>
                    </tr>
                    <tr>
                        <td>
                            <input type="submit" value="插入"/>
                        </td>
                        <td>
                            <input type="reset" value="重置"/>
                        </td>
                    </tr>
                </tbody>
            </table>
        </form>
    </body>
    </html>

删除用户

func (this *DeleteUserController) Get1() {
    	//通过id删除
    	//http://localhost:8080/deleteuser?id=2
    	//获取id
    	id, err := this.GetInt("id")
    	if err != nil {
    		this.Ctx.WriteString("删除失败!")
    		return
    	}
    	//创建user对象
    	user := models.User{Id:id}
    	orm := orm.NewOrm()
    	//delete函数默认根据id进行删除，也可以根据指定的字段进行删除
    	//DELETE FROM USER WHERE id = 2;
    	n, err := orm.Delete(&user)
    	if n > 0 && err == nil {
    		this.Ctx.WriteString("删除成功!")
    		return
    	}else {
    		this.Ctx.WriteString("删除失败!")
    	}
    }
    
    func (this *DeleteUserController) Get() {
    
    	//通过姓名删除
    	//http://localhost:8080/deleteuser?name=admin
    	name := this.GetString("name")
    	user := models.User{Name:name}
    
    	//创建orm对象
    	orm := orm.NewOrm()
    	//delete函数默认根据id进行删除，也可以根据指定的字段进行删除
    	//DELETE FROM USER WHERE NAME='Alice';
    	n, err := orm.Delete(&user, "name")
    	if n > 0 && err == nil {
    		this.Ctx.WriteString("删除成功!")
    		return
    	}else {
    		this.Ctx.WriteString("删除失败!")
    	}
    }

查询用户

func (this *QueryUserController) Get1() {
    	//获取id查询用户
    	//http://localhost:8080/queryuser?id=2
    	id, err := this.GetInt("id")
    	if err != nil {
    		this.Ctx.WriteString("查询出错!")
    		return
    	}
    	user := models.User{Id:id}
    
    	//创建orm
    	orm := orm.NewOrm()
    	//默认根据id查询
    	//SELECT * FROM USER WHERE id = 4;
    	err = orm.Read(&user)
    	if err != nil {
    		this.Ctx.WriteString("查询出错!")
    		return
    	}else {
    		this.Ctx.WriteString("id = " + strconv.Itoa(user.Id) + "\nname = " +
    			user.Name + "\nage = " + strconv.Itoa(user.Age) + "\nnickname = " + user.Nickname)
    	}
    }
    
    
    func (this *QueryUserController) Get() {
    	//http://localhost:8080/queryuser?name=admin
    	//获取用户输入的姓名
    	name := this.GetString("name")
    	//构造user
    	user := models.User{Name:name}
    	//创建orm
    	orm := orm.NewOrm()
    	//根据name查询用户，Read函数如果不指定参数
    	//SELECT * FROM USER WHERE NAME = '吴俏祥';
    	err := orm.Read(&user, "name")
    	if err != nil {
    		this.Ctx.WriteString("查询出错!")
    		return
    	}else {
    		this.Ctx.WriteString("id = " + strconv.Itoa(user.Id) + "\nname = " +
    			user.Name + "\nage = " + strconv.Itoa(user.Age) + "\nnickname = " + user.Nickname)
    	}
    }

更新用户

//http://localhost:8080/updateuser?id=1&name=tom&nickname=234&age=23
    func (this *UpdateUserController) Get1() {
    	id, err := this.GetInt("id")//获取id
    	if err != nil {
    		this.Ctx.WriteString("更新失败!")
    		return
    	}
    	name := this.GetString("name")//获取姓名
    	nickname := this.GetString("nickname")//获取昵称
    	age, err := this.GetInt("age")
    	if err != nil {
    		this.Ctx.WriteString("更新失败!")
    		return
    	}
    	user := models.User{Id:id, Name:name, Nickname:nickname, Age:age}
    	//UPDATE USER SET NAME = '杜紫维' WHERE id = 1;
    	//user := models.User{Id:id, Name:name, Nickname:nickname}
    	orm := orm.NewOrm()
    	//update函数根据对象的id进行更新,必须指定id
    	n, err := orm.Update(&user)
    	if n > 0 && err == nil {
    		this.Ctx.WriteString("更新成功!")
    	}else {
    		this.Ctx.WriteString("更新失败!")
    	}
    }
    
    
    
    //http://localhost:8080/updateuser?id=1&name=tom&nickname=234&age=23
    func (this *UpdateUserController) Get() {
    	id, err := this.GetInt("id")//获取id
    	if err != nil {
    		this.Ctx.WriteString("更新失败!")
    		return
    	}
    	name := this.GetString("name")//获取姓名
    	nickname := this.GetString("nickname")//获取昵称
    	age, err := this.GetInt("age")
    	if err != nil {
    		this.Ctx.WriteString("更新失败!")
    		return
    	}
    	user := models.User{Id:id, Name:name, Nickname:nickname, Age:age}
    	//UPDATE USER SET NAME = '杜紫维' WHERE id = 1;
    	//user := models.User{Id:id, Name:name, Nickname:nickname}
    	orm := orm.NewOrm()
    	//update函数根据指定字段进行更新,且必须指定id
    	n, err := orm.Update(&user, "name")
    	if n > 0 && err == nil {
    		this.Ctx.WriteString("更新成功!")
    	}else {
    		this.Ctx.WriteString("更新失败!")
    	}
    }

插入订单

func (this *InserOrderController) Get(){
    	//创建orm
    	orm := orm.NewOrm()
    	//创建订单
    	order := models.Userorder{}
    	//对订单初始化
    	order.Orderdata = "this is order123"
    	order.User = &models.User{Id:6}
    	//如果不指定Id，可以插入成功，但是外键user_id为0
    	//order.User = &models.User{Name:"吴俏祥"}
    	//插入订单
    	n, err := orm.Insert(&order)
    	//判断是否插入成功
    	if n > 0 && err != nil {
    		this.Ctx.WriteString("插入失败!")
    		return
    	}
    	this.Ctx.WriteString("插入成功!")
    }

查询订单

func (this *QueryOrderController) Get(){
    	orm := orm.NewOrm()
    	//可以传递表名(大小写无关)和对象名
    	qs := orm.QueryTable("Userorder")
    	var orders []*models.Userorder
    	//SELECT * FROM userorder WHERE user_id = 1;
    	order_num, err := qs.Filter("user__id", 1).All(&orders)//user__id=user.id
    	if err != nil {
    		this.Ctx.WriteString("query order fail！")
    		return
    	}
    	fmt.Println("order_num = ", order_num)
    	for _, order := range orders {
    		fmt.Println("order = ", order)
    	}
    	this.Ctx.WriteString("查询成功!")
    }

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