update

Author: Guo-Zhang

dart_language/async.md

@@ -0,0 +1,48 @@
+# 异步
+
+同步写法：
+
+```dart
+// This example uses the Google Books API to search
+// for books about HTTP. For details, see
+// https://developers.google.com/books/docs/overview
+final url = Uri.https(
+  'www.googleapis.com',
+  '/books/v1/volumes',
+  {'q': '{http}'},
+);
+
+// Await the HTTP GET response
+// and print the response body.
+http.get(url).then((result)=>print(result.body));
+```
+
+修改自[DartPad提供的样例](https://dartpad.cn/?id=4a68e553746602d851ab3da6aeafc3dd)。
+
+## Flutter
+
+https://api.flutter.dev/flutter/widgets/FutureBuilder-class.html
+
+```dart
+Widget buildOutput(input){
+  return FutureBuilder(
+    // https://api.flutter.dev/flutter/widgets/FutureBuilder-class.html
+    future: executor.execute(input),
+    builder: (BuildContext context, AsyncSnapshot<dynamic> snapshot) {
+    if (snapshot.connectionState == ConnectionState.done) {
+        // 请求已结束
+        if (snapshot.hasError) {
+        // 请求失败，显示错误
+        return Text("Error: ${snapshot.error}");
+        } else {
+        // 请求成功，显示数据
+        return Text("${snapshot.data}");
+        }
+    } else {
+        // 请求未结束，显示正在加载的状态
+        return const Text('代码运行中...');
+    }
+    },
+  );
+}
+```

http/cors.md

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+# CORS策略解决方案
+
+本地调试时关闭Chrome的检查：
+- https://pub.dev/packages/flutter_cors
+- https://stackoverflow.com/questions/65630743/how-to-solve-flutter-web-api-cors-error-only-with-dart-code
+
+如果`fluttercors`不可用，运行
+
+```shell
+export PATH="$PATH":"$HOME/.pub-cache/bin"
+```
+
+把命令行工具的执行路径加入配置。

packages_and_plugins/Project_Structure.md

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+# 版本
+
+<!-- 需要找到官方文档验证 -->
+
+> In Dart conventions the +1 is used when publishing a patch release where the first number in the version is 0.
+
+https://stackoverflow.com/questions/53626418/what-does-plus-one-1-mean-in-darts-dependency-versioning