Golang 反射如何与泛型特性结合使用_Golang 类型参数与动态反射示例

func Inspect[T any](v T) {
    rv := reflect.ValueOf(v)
    rt := reflect.TypeOf(v)

    fmt.Printf("Type: %s\n", rt)
    fmt.Printf("Kind: %s\n", rt.Kind())
    
    if rt.Kind() == reflect.Struct {
        fmt.Printf("Fields count: %d\n", rv.NumField())
        for i := 0; i < rv.NumField(); i++ {
            field := rt.Field(i)
            fmt.Printf("Field %d: %s (%s)\n", i, field.Name, field.Type)
        }
    }
}

type Person struct {
    Name string
    Age  int
}

Inspect(Person{"Alice", 30})
// 输出：
// Type: main.Person
// Kind: struct
// Fields count: 2
// Field 0: Name (string)
// Field 1: Age (int)

func CallInspectByReflect(v interface{}) {
    // 获取泛型函数针对具体类型的反射对象
    inspectFunc := reflect.ValueOf(Inspect[interface{}])
    
    // 调用函数，传入 v
    inspectFunc.Call([]reflect.Value{reflect.ValueOf(v)})
}

func Validate[T any](v T) []string {
    var errors []string
    rv := reflect.ValueOf(v)
    rt := reflect.TypeOf(v)

    if rt.Kind() != reflect.Struct {
        return append(errors, "input must be a struct")
    }

    for i := 0; i < rv.NumField(); i++ {
        field := rt.Field(i)
        value := rv.Field(i)

        if tag := field.Tag.Get("required"); tag == "true" {
            if value.Interface() == reflect.Zero(value.Type()).Interface() {
                errors = append(errors, fmt.Sprintf("field %s is required", field.Name))
            }
        }
    }
    return errors
}

type User struct {
    Name string `required:"true"`
    Age  int    `required:"false"`
    Email string `required:"true"`
}

u := User{Name: "", Email: ""}
fmt.Println(Validate(u)) 
// 输出: [field Name is required]