From f4bda4f434615809f88033335861171026e6b3c8 Mon Sep 17 00:00:00 2001
From: openapphub <openapphub@outlook.com>
Date: Wed, 5 Nov 2025 15:55:50 +0800
Subject: [PATCH] fix: Example23 class When used as a mixin, it throws an
 error.

Before Dart 2.1: Use a regular class without a constructor as a mixin. It is recommended to use mixin for the new project
---
 zh-cn/dart.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/zh-cn/dart.md b/zh-cn/dart.md
index fb52dd359a..2f4ba4d3d8 100644
--- a/zh-cn/dart.md
+++ b/zh-cn/dart.md
@@ -327,8 +327,9 @@ example22() {
 // Mixin 主要是用来和辅助的类共享方法的，
 // 这样单一继承就不会影响代码复用。
 // Mixin 声明在类定义的 "with" 关键词后面。
+// 在 Dart 2.1 之前：把一个普通的、没有构造函数的 class 当作 mixin 使用。新项目推荐使用 mixin
 class Example23A {}
-class Example23Utils {
+mixin Example23Utils {
   addTwo(n1, n2) {
     return n1 + n2;
   }