update: 适配任意消息元素的可能状况，除纯文本以外所有元素都可以拥有任意属性以及子元素且可以获取，同时删除了输出内容

pkg/message/message_element.go

@@ -1,5 +1,9 @@
 package message
 
+import (
+	"golang.org/x/net/html"
+)
+
 type MessageElement interface {
 	Tag() string
 	Stringify() string
@@ -31,9 +35,54 @@ func (e *ChildrenMessageElement) stringifyChildren() string {
 	return result
 }
 
-func (e *ChildrenMessageElement) stringifyByTag(tag string) string {
-	if e == nil || len(e.Children) == 0 {
-		return "<" + tag + " />"
+func (e *ChildrenMessageElement) parseChildren(n *html.Node) (*ChildrenMessageElement, error) {
+	var children []MessageElement
+	err := parseHtmlChildrenNode(n, func(e MessageElement) {
+		children = append(children, e)
+	})
+	if err != nil {
+		return nil, err
+	}
+	result := &ChildrenMessageElement{
+		Children: children,
+	}
+	return result, nil
+}
+
+type ExtendAttributes struct {
+	Attributes map[string]string
+}
+
+func (e *ExtendAttributes) AddAttribute(key, value string) *ExtendAttributes {
+	result := e
+	if result == nil {
+		result = &ExtendAttributes{
+			Attributes: make(map[string]string),
+		}
 	}
-	return "<" + tag + ">" + e.stringifyChildren() + "</" + tag + ">"
+	result.Attributes[key] = value
+	return result
+}
+
+func (e *ExtendAttributes) Get(key string) (string, bool) {
+	if e == nil {
+		return "", false
+	}
+	v, ok := e.Attributes[key]
+	return v, ok
+}
+
+func (e *ExtendAttributes) stringifyAttributes() string {
+	if e == nil || len(e.Attributes) == 0 {
+		return ""
+	}
+	var result string
+	for k, v := range e.Attributes {
+		if v == "" {
+			result += " " + k
+		} else {
+			result += " " + k + `="` + escape(v, true) + `"`
+		}
+	}
+	return result
 }

pkg/message/message_element_basic.go

@@ -33,6 +33,8 @@ func (e *MessageElementText) Parse(n *html.Node) (MessageElement, error) {
 
 type MessageElementAt struct {
 	*noAliasMessageElement
+	*ChildrenMessageElement
+	*ExtendAttributes
 	Id   string
 	Name string //	收发	目标用户的名称
 	Role string //	收发	目标角色
@@ -44,7 +46,7 @@ func (e *MessageElementAt) Tag() string {
 }
 
 func (e *MessageElementAt) Stringify() string {
-	result := "<" + e.Tag()
+	result := ""
 	if e.Id != "" {
 		result += ` id="` + escape(e.Id, true) + `"`
 	}
@@ -57,21 +59,39 @@ func (e *MessageElementAt) Stringify() string {
 	if e.Type != "" {
 		result += ` type="` + escape(e.Type, true) + `"`
 	}
-	return result + "/>"
+	result += e.stringifyAttributes()
+	childrenStr := e.stringifyChildren()
+	if childrenStr == "" {
+		return `<` + e.Tag() + result + `/>`
+	}
+	return `<` + e.Tag() + result + `>` + childrenStr + `</` + e.Tag() + `>`
 }
 
 func (e *MessageElementAt) Parse(n *html.Node) (MessageElement, error) {
 	attrMap := attrList2MapVal(n.Attr)
-	return &MessageElementAt{
+	result := &MessageElementAt{
 		Id:   attrMap["id"],
 		Name: attrMap["name"],
 		Role: attrMap["role"],
 		Type: attrMap["type"],
-	}, nil
+	}
+	for key, value := range attrMap {
+		if key != "id" && key != "name" && key != "role" && key != "type" {
+			result.ExtendAttributes = result.AddAttribute(key, value)
+		}
+	}
+	children, err := result.parseChildren(n)
+	if err != nil {
+		return nil, err
+	}
+	result.ChildrenMessageElement = children
+	return result, nil
 }
 
 type MessageElementSharp struct {
 	*noAliasMessageElement
+	*ChildrenMessageElement
+	*ExtendAttributes
 	Id   string //收发	目标频道的 ID
 	Name string //收发	目标频道的名称
 }
@@ -81,26 +101,44 @@ func (e *MessageElementSharp) Tag() string {
 }
 
 func (e *MessageElementSharp) Stringify() string {
-	result := "<" + e.Tag()
+	result := ""
 	if e.Id != "" {
 		result += ` id="` + escape(e.Id, true) + `"`
 	}
 	if e.Name != "" {
 		result += ` name="` + escape(e.Name, true) + `"`
 	}
-	return result + "/>"
+	result += e.stringifyAttributes()
+	childrenStr := e.stringifyChildren()
+	if childrenStr == "" {
+		return `<` + e.Tag() + result + `/>`
+	}
+	return `<` + e.Tag() + result + `>` + childrenStr + `</` + e.Tag() + `>`
 }
 
 func (e *MessageElementSharp) Parse(n *html.Node) (MessageElement, error) {
 	attrMap := attrList2MapVal(n.Attr)
-	return &MessageElementSharp{
+	result := &MessageElementSharp{
 		Id:   attrMap["id"],
 		Name: attrMap["name"],
-	}, nil
+	}
+	for key, value := range attrMap {
+		if key != "id" && key != "name" && key != "role" && key != "type" {
+			result.ExtendAttributes = result.AddAttribute(key, value)
+		}
+	}
+	children, err := result.parseChildren(n)
+	if err != nil {
+		return nil, err
+	}
+	result.ChildrenMessageElement = children
+	return result, nil
 }
 
 type MessageElementA struct {
 	*noAliasMessageElement
+	*ChildrenMessageElement
+	*ExtendAttributes
 	Href string
 }
 
@@ -109,17 +147,33 @@ func (e *MessageElementA) Tag() string {
 }
 
 func (e *MessageElementA) Stringify() string {
-	result := "<" + e.Tag()
+	result := ""
 	if e.Href != "" {
 		result += ` href="` + escape(e.Href, true) + `"`
 	}
-	return result + "/>"
+	result += e.stringifyAttributes()
+	childrenStr := e.stringifyChildren()
+	if childrenStr == "" {
+		return `<` + e.Tag() + result + `/>`
+	}
+	return `<` + e.Tag() + result + `>` + childrenStr + `</` + e.Tag() + `>`
 }
 func (e *MessageElementA) Parse(n *html.Node) (MessageElement, error) {
 	attrMap := attrList2MapVal(n.Attr)
-	return &MessageElementA{
+	result := &MessageElementA{
 		Href: attrMap["href"],
-	}, nil
+	}
+	for key, value := range attrMap {
+		if key != "href" {
+			result.ExtendAttributes = result.AddAttribute(key, value)
+		}
+	}
+	children, err := result.parseChildren(n)
+	if err != nil {
+		return nil, err
+	}
+	result.ChildrenMessageElement = children
+	return result, nil
 }
 
 func init() {