type User struct {
  ID string `param:"id" query:"id" form:"id" json:"id" xml:"id"`
}

if err := (&DefaultBinder{}).BindPathParams(c, &payload); err != nil {
  return err
}

if err := (&DefaultBinder{}).BindQueryParams(c, &payload); err != nil {
  return err
}

if err := (&DefaultBinder{}).BindBody(c, &payload); err != nil {
  return err
}

curl --location --request POST 'http://localhost:8080/users' \
--header 'Content-Type: application/json' \
--data-raw '{"name":"wangxin","email":"[email protected]"}'

curl --location --request POST 'http://localhost:8080/users' \
--form 'name="wangxin"' \
--form 'email="[email protected]"'

type User struct {
	Name  string `json:"name" form:"name" query:"name"`
	Email string `json:"email" form:"email" query:"email"`
}

func GetUser(c echo.Context) error {
	// 进行数据绑定
	u := new(model.User)
	if err := c.Bind(u); err != nil {
		return err
	}
	// 安全保障将绑定的信息进行拷贝
	user := &model.UserDTO{
		Name:    u.Name,
		Email:   u.Email,
		IsLogin: false,
	}
	// 以json的形式返回数据
	return c.JSON(http.StatusOK, user)
}

<Type>("param", &destination) // 如果请求中该 param 参数存在则将其绑定到 Type 类型的 destination 目标对象中
Must<Type>("param", &destination) // 在请求中该参数必须存在
<Type>s("param", &destination) // 针对切片目标对象进行绑定
Must<Type>s("param", &destination) // 针对切片目标对象必须存在于请求参数中

// url =  "/api/search?active=true&id=1&id=2&id=3&length=25"
var opts struct {
  IDs []int64
  Active bool
}
length := int64(50) // default length is 50

// creates query params binder that stops binding at first error
err := echo.QueryParamsBinder(c).
  Int64("length", &length).
  Int64s("ids", &opts.IDs).
  Bool("active", &opts.Active).
  BindError() // returns first binding error

type Binder interface{
  Bind(i interface{}, c Context) error
}

func (b *DefaultBinder) Bind(i interface{}, c Context) (err error) {
	if err := b.BindPathParams(c, i); err != nil {
		return err
	}
	// Issue #1670 - Query params are binded only for GET/DELETE and NOT for usual request with body (POST/PUT/PATCH)
	// Reasoning here is that parameters in query and bind destination struct could have UNEXPECTED matches and results due that.
	// i.e. is `&id=1&lang=en` from URL same as `{"id":100,"lang":"de"}` request body and which one should have priority when binding.
	// This HTTP method check restores pre v4.1.11 behavior and avoids different problems when query is mixed with body
	if c.Request().Method == http.MethodGet || c.Request().Method == http.MethodDelete {
		if err = b.BindQueryParams(c, i); err != nil {
			return err
		}
	}
	return b.BindBody(c, i)
}

func (b *DefaultBinder) BindBody(c Context, i interface{}) (err error) {
	req := c.Request()
	if req.ContentLength == 0 {
		return
	}

	ctype := req.Header.Get(HeaderContentType)
	switch {
	case strings.HasPrefix(ctype, MIMEApplicationJSON):
		if err = json.NewDecoder(req.Body).Decode(i); err != nil {
			if ute, ok := err.(*json.UnmarshalTypeError); ok {
				return NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Unmarshal type error: expected=%v, got=%v, field=%v, offset=%v", ute.Type, ute.Value, ute.Field, ute.Offset)).SetInternal(err)
			} else if se, ok := err.(*json.SyntaxError); ok {
				return NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Syntax error: offset=%v, error=%v", se.Offset, se.Error())).SetInternal(err)
			}
			return NewHTTPError(http.StatusBadRequest, err.Error()).SetInternal(err)
		}
	case strings.HasPrefix(ctype, MIMEApplicationXML), strings.HasPrefix(ctype, MIMETextXML):
		if err = xml.NewDecoder(req.Body).Decode(i); err != nil {
			if ute, ok := err.(*xml.UnsupportedTypeError); ok {
				return NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Unsupported type error: type=%v, error=%v", ute.Type, ute.Error())).SetInternal(err)
			} else if se, ok := err.(*xml.SyntaxError); ok {
				return NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Syntax error: line=%v, error=%v", se.Line, se.Error())).SetInternal(err)
			}
			return NewHTTPError(http.StatusBadRequest, err.Error()).SetInternal(err)
		}
	case strings.HasPrefix(ctype, MIMEApplicationForm), strings.HasPrefix(ctype, MIMEMultipartForm):
		params, err := c.FormParams()
		if err != nil {
			return NewHTTPError(http.StatusBadRequest, err.Error()).SetInternal(err)
		}
		if err = b.bindData(i, params, "form"); err != nil {
			return NewHTTPError(http.StatusBadRequest, err.Error()).SetInternal(err)
		}
	default:
		return ErrUnsupportedMediaType
	}
	return nil
}

func (b *DefaultBinder) bindData(destination interface{}, data map[string][]string, tag string) error {
	if destination == nil || len(data) == 0 {
		return nil
	}
	typ := reflect.TypeOf(destination).Elem()
	val := reflect.ValueOf(destination).Elem()

	// Map
	if typ.Kind() == reflect.Map {
		for k, v := range data {
			val.SetMapIndex(reflect.ValueOf(k), reflect.ValueOf(v[0]))
		}
		return nil
	}

	// !struct
	if typ.Kind() != reflect.Struct {
		if tag == "param" || tag == "query" {
			// incompatible type, data is probably to be found in the body
			return nil
		}
		return errors.New("binding element must be a struct")
	}

	for i := 0; i < typ.NumField(); i++ {
		typeField := typ.Field(i)
		structField := val.Field(i)
		if !structField.CanSet() {
			continue
		}
		structFieldKind := structField.Kind()
		inputFieldName := typeField.Tag.Get(tag)

		if inputFieldName == "" {
			// If tag is nil, we inspect if the field is a not BindUnmarshaler struct and try to bind data into it (might contains fields with tags).
			// structs that implement BindUnmarshaler are binded only when they have explicit tag
			if _, ok := structField.Addr().Interface().(BindUnmarshaler); !ok && structFieldKind == reflect.Struct {
				if err := b.bindData(structField.Addr().Interface(), data, tag); err != nil {
					return err
				}
			}
			// does not have explicit tag and is not an ordinary struct - so move to next field
			continue
		}

		inputValue, exists := data[inputFieldName]
		if !exists {
			// Go json.Unmarshal supports case insensitive binding.  However the
			// url params are bound case sensitive which is inconsistent.  To
			// fix this we must check all of the map values in a
			// case-insensitive search.
			for k, v := range data {
				if strings.EqualFold(k, inputFieldName) {
					inputValue = v
					exists = true
					break
				}
			}
		}

		if !exists {
			continue
		}

		// Call this first, in case we're dealing with an alias to an array type
		if ok, err := unmarshalField(typeField.Type.Kind(), inputValue[0], structField); ok {
			if err != nil {
				return err
			}
			continue
		}

		numElems := len(inputValue)
		if structFieldKind == reflect.Slice && numElems > 0 {
			sliceOf := structField.Type().Elem().Kind()
			slice := reflect.MakeSlice(structField.Type(), numElems, numElems)
			for j := 0; j < numElems; j++ {
				if err := setWithProperType(sliceOf, inputValue[j], slice.Index(j)); err != nil {
					return err
				}
			}
			val.Field(i).Set(slice)
		} else if err := setWithProperType(typeField.Type.Kind(), inputValue[0], structField); err != nil {
			return err

		}
	}
	return nil
}

type User struct {
    Name string `query:"name" form:"name" json:"name" xml:"name"`
    Sex  string `query:"sex" form:"sex" json:"sex" xml:"sex"`
}

func TestBinder(c echo.Context) error{
    user := &User{}
    if err := c.Bind(user);err != nil{
        return err
    }
    return c.Json(http.StatusOK,user)
}

type MsgpackBinder struct {
}

// Bind 实现接口
func (binder *MsgpackBinder) Bind(i interface{}, c echo.Context) (err error) {

	// 支持默认的binder
	db := new(echo.DefaultBinder)
	if err1 := db.Bind(i, c); err1 != echo.ErrUnsupportedMediaType {
		// 默认解析成功返回
		return
	}
	// 获取请求数据
	request := c.Request()
	// 获取请求数据类型
	ctype := request.Header.Get(echo.HeaderContentType)
	// 针对msgpack类型的数据进行解析
	if strings.HasPrefix(ctype, echo.MIMEApplicationMsgpack) {
		if err := msgpack.NewDecoder(request.Body).Decode(i); err != nil {
			return echo.NewHTTPError(http.StatusBadRequest, err.Error()).SetInternal(err)
		}
		// 解析成功返回
		return
	}
	// 不支持的类型
	return echo.ErrUnsupportedMediaType
}

func main() {
	e := echo.New()
	// 使用自定义Binder
	e.Binder = new(models.MsgpackBinder)
	e.POST("/", func(context echo.Context) error {
		user := new(models.User)
		if err := context.Bind(user); err != nil {
			return err
		}
		return context.JSON(http.StatusOK, user)
	})
	e.Logger.Fatal(e.Start(":8080"))
}

func main() {
	// 发送数据
	type User struct {
		Name string
		Sex  string
	}

	data, err := msgpack.Marshal(&User{Name: "wangxin", Sex: "male"})
	if err != nil {
		panic(err)
	}

	response, err := http.DefaultClient.Post("http://localhost:8080/", "application/msgpack", bytes.NewReader(data))
	if err != nil {
		panic(err)
	}
	// 延迟关闭读写流
	defer response.Body.Close()

	// 读取响应数据
	result, err := ioutil.ReadAll(response.Body)
	if err != nil {
		panic(err)
	}
	// 输出响应数据
	fmt.Printf("%s\n", result)
}