一、 as 、 hide 、show

 import 'package:http/http.dart' as http;

as:其中as是为了解决方法名冲突的问题！通过重命名。方法名 调用
hide:隐藏某个不要导入的方法
show:只导入某些内容

二、在pubspec里面的配置

#项目名称
name: wechat_flutter_demo
#项目描述
description: A new Flutter application.

# The following line prevents the package from being accidentally published to
# pub.dev using `pub publish`. This is preferred for private packages.
publish_to: 'none' # Remove this line if you wish to publish to pub.dev

# The following defines the version and build number for your application.
# A version number is three numbers separated by dots, like 1.2.43
# followed by an optional build number separated by a +.
# Both the version and the builder number may be overridden in flutter
# build by specifying --build-name and --build-number, respectively.
# In Android, build-name is used as versionName while build-number used as versionCode.
# Read more about Android versioning at https://developer.android.com/studio/publish/versioning
# In iOS, build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
# Read more about iOS versioning at
# https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
#项目版本号
version: 1.0.0+1

environment:
  sdk: ">=2.7.0 <3.0.0"

#打包的时候回添加进去，项目第三方插件
dependencies:
  flutter:
    sdk: flutter


  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^1.0.0
  http: 0.12.2
  dio: ^3.0.9
  # dio: ^3.0.9 ->表示大版本不变的区间写法，相当于'>=3.0.9 < 4.0.0'
  # dio: 3.0.9 -> 指定版本
  # dio: any -> 任意版本
  # dio: ">=3.0.9 <4.0.0" 大于等于 小于