继承 封装 多态
定义结构体
//定义老师的结构体
type Teacher struct {Name stringAge intSchool string
}func main() {var t1 Teacherfmt.Println(t1)t1.Name = "tom"t1.Age = 20t1.School = "school"fmt.Println(t1)
}
结构体实例的创建
package mainimport "fmt"//定义老师的结构体
type Teacher struct {Name stringAge intSchool string
}func main() {var t1 Teacherfmt.Println(t1)t1.Name = "tom"t1.Age = 20t1.School = "school"fmt.Println(t1)var t2 Teacher = Teacher{"liu", 32, "rrr"}fmt.Println(t2)//指针*var t *Teacher = new(Teacher)//t是指针 t其实指向的就是地址 应该给这个地址的执行的对象的字段赋值(*t).Name = "ma"(*t).Age = 23t.School = "daxue"fmt.Println(t)var t6 *Teacher = &Teacher{"sa", 46, "eda"}fmt.Println(t6)
}
//指针*
结构值之间的转换
方法 行为
package mainimport "fmt"//定义Person结构体
type Person struct {Name string
}func (p Person) test() {fmt.Println(p.Name)
}
func main() {//创建结构体对象var p Personp.Name = "tom"p.test()
}
改变值
package mainimport "fmt"//定义Person结构体
type Person struct {Name string
}func (p Person) test() {fmt.Println(p.Name)
}//*是指针
func (p *Person) test01() {fmt.Println()fmt.Println((*p).Name)
}
func main() {//创建结构体对象var p Personp.Name = "tom"p.test()p.Name = "sasa"fmt.Printf("p的地址为：%p \n", &p)(&p).test()fmt.Println(p)
}
改变值用指针
package mainimport "fmt"type interger intfunc (i interger) print() {fmt.Println("i= ", i)
}func (i *interger) print01() {(*i) = 30fmt.Println("i=", *i)
}
func main() {var i interger = 20i.print()fmt.Println(i)var i01 interger = 5i01.print01()fmt.Println("i01=", i01)
}
其他包被访问用大写
toString
package mainimport "fmt"type Student struct {Name stringAge int
}func (s Student) toString() string {str := fmt.Sprintf("Name = %v, Age = %v", s.Name, s.Age)return str
}
func (s *Student) toString2() string {str := fmt.Sprintf("Name = %v, Age = %v", s.Name, s.Age)return str
}func main() {stu := Student{Name: "tom",Age: 20,}fmt.Println(stu)fmt.Println(&stu)
}
方法和函数的区别
import "fmt"type Student struct {Name string
}//定义方法必须定义指定的类型
func (s Student) test01() {fmt.Println(s.Name)
}//定义函数
func method01(s Student) {fmt.Println(s.Name)
}
func main() {//调用函数var s Student = Student{"tom"}method01(s)//方法调用s.test01()
}函数定义的是指针必须传递的是指针，函数定义的是值传递 必须是值类型
package mainimport "fmt"type Student struct {Name string
}//定义函数
func method01(s Student) {fmt.Println(s.Name)
}func method02(s *Student) {fmt.Println((*s).Name)
}
func main() {//函数定义的是指针必须传递的是指针//函数定义的是值传递 必须是值类型var s Student = Student{"tom"}method01(s)method02(&s)
}
对于方法来说，接收者为值类型，可以传入指针类型，接受者为指针类型，可以传入值类型
package mainimport "fmt"type Student struct {Name string
}//定义方法
func (s Student) test01() {fmt.Println(s.Name)
}
func (s *Student) test02() {fmt.Println((*s).Name)
}func main() {var s Student = Student{"yy"}s.test01()//虽然用指针类型调用，但是传递还是安装值传递的形式(&s).test01()(&s).test02()s.test02()
}
创建结构体实例时指定字段值
返回值的
跨包的使用
package kua01type Student struct {Name string
}package mainimport ("encoding/json""fmt""testgo/oop/kuabaonew/kua01"
)func main() {//跨包创建结构体student实例var s kua01.Student = kua01.Student{Name: "tom"}fmt.Println(s)var js, _ = json.Marshal(s)jsonStr := string(js)fmt.Println("将结构体转json:--->>" + jsonStr)st := kua01.Student{Name: "red"}fmt.Println(st)var stjson, _ = json.Marshal(st)jsonstr := string(stjson)fmt.Println(jsonstr)var student kua01.Studenterr := json.Unmarshal([]byte(jsonstr), &student)if err != nil {fmt.Printf("unmarshal err=%v\n", err)}fmt.Printf("反序列化后student=%#v student.Name=%v \n", student, student.Name)}
结构体tag
package mainimport ("encoding/json""fmt"
)type Student struct {ID intGender stringName string
}type Class struct {Title stringStudent []Student
}func main() {c := &Class{Title: "001",Student: make([]Student, 0, 200),}for i := 0; i < 10; i++ {stu := Student{Name: fmt.Sprintf("stu%02d", i),Gender: "男",ID: i,}c.Student = append(c.Student, stu)}data, err := json.Marshal(c)if err != nil {fmt.Println("json marshal failed")return}fmt.Printf("json:%s \n", data)str := `{"Title":"001","Student":[{"ID":0,"Gender":"男","Name":"stu00"},{"ID":1,"Gender":"男","Name":"stu01"},{"ID":2,"Gender":"男","Name":"stu02"},{"ID":3,"Gender":"男","Name":"stu03"},{"ID":4,"Gender":"男","Name":"stu04"},{"ID":5,"Gender":"男","Name":"stu05"},{"ID":6,"Gender":"男","Name":"stu06"},{"ID":7,"Gender":"男","Name":"stu07"},{"ID":8,"Gender":"男","Name":"stu08"},{"ID":9,"Gender":"男","Name":"stu09"}]}`c1 := &Class{}err0 := json.Unmarshal([]byte(str), c1)if err0 != nil {fmt.Println("json unmarshal failed!")return}fmt.Printf("%#v\n", c1)
}
工厂模式的创建
package factory01type student struct {Name stringAge int
}//工厂模式
func NewStudent(n string, a int) *student {return &student{n, a}
}
package mainimport ("encoding/json""fmt""testgo/oop/factory/factory01"
)func main() {//跨包创建结构体Student的实例s := factory01.NewStudent("tom", 20)data, _ := json.Marshal(s)jsonStr := string(data)fmt.Printf("json ", jsonStr)
}
