为更简单的方式为网络和应用程序。试试这个

import 'dart:io' show Platform;
import 'package:flutter/foundation.dart' show kIsWeb;


var platformName = '';
if (kIsWeb) {
  platformName = "Web";
} else {
  if (Platform.isAndroid) {
    platformName = "Android";
  } else if (Platform.isIOS) {
    platformName = "IOS";
  } else if (Platform.isFuchsia) {
    platformName = "Fuchsia";
  } else if (Platform.isLinux) {
    platformName = "Linux";
  } else if (Platform.isMacOS) {
    platformName = "MacOS";
  } else if (Platform.isWindows) {
    platformName = "Windows";
  }
}
print("platformName :- "+platformName.toString());

你可以这样做

defaultTargetPlatform == TargetPlatform.iOS
          ? kIOSTheme
          : kDefaultTheme,

从导入'包:flutter/foundation.dart';

if (Platform.isAndroid) {
  // Android-specific code/UI Component
} else if (Platform.isIOS) {
  // iOS-specific code/UI Component
}

不要忘记导入IO库。

import 'dart:io';

如果你使用导入'dart:html';那么你必须指定平台定义，因为两个库都有“平台”的定义

在这种情况下，使用如下所示的平台特定代码:

import 'dart:io' as IO;
import 'dart:html';

if (IO.Platform.isAndroid) {
  // Android-specific code/UI Component
} else if (IO.Platform.isIOS) {
  // iOS-specific code/UI Component
}

如果你正在寻找合适的平台集成，我建议在Flutter网站上使用完整的示例: https://flutter.dev/docs/development/platform-integration/platform-channels

虽然defaultTargetPlatform可以工作，但我建议使用Theme.of(context). targetplatform。这样可以测试iOS行为(因为defaultTargetPlatform总是TargetPlatform)。Android正在测试中)。它还允许小部件的祖先通过将其包装在Theme小部件中来覆盖其目标平台。

这个自定义创建的类将帮助您检测平台:

import 'package:flutter/foundation.dart'
    show defaultTargetPlatform, kIsWeb, TargetPlatform;

enum Os {
  web,
  android,
  ios,
  macOS,
  linux,
  windows,
  fuchsia,
}

class Platform {
  const Platform();

  /// Platform is Web.
  static bool get isWeb => os == Os.web;

  /// Platform is Android.
  static bool get isAndroid => os == Os.android;

  /// Platform is IOS.
  static bool get isIOS => os == Os.ios;

  /// Platform is Fuchsia.
  static bool get isFuchsia => os == Os.fuchsia;

  /// Platform is Linux.
  static bool get isLinux => os == Os.linux;

  /// Platform is MacOS.
  static bool get isMacOS => os == Os.macOS;

  /// Platform is Windows.
  static bool get isWindows => os == Os.windows;

  /// Platform is Android or IOS.
  static bool get isMobile => isAndroid || isIOS;

  /// Platform is Android or IOS or Fuchsia.
  static bool get isFullMobile => isMobile || isFuchsia;

  /// Platform is Linux or Windows or MacOS.
  static bool get isDesktop => isLinux || isWindows || isMacOS;

  /// Getting the os name.
  static Os get os {
    if (kIsWeb) {
      return Os.web;
    }
    switch (defaultTargetPlatform) {
      case TargetPlatform.android:
        return Os.android;
      case TargetPlatform.iOS:
        return Os.ios;
      case TargetPlatform.macOS:
        return Os.macOS;
      case TargetPlatform.windows:
        return Os.windows;
      case TargetPlatform.fuchsia:
        return Os.fuchsia;
      case TargetPlatform.linux:
        return Os.linux;
    }
  }
}

感谢科林，最终答案是:

bool isIOS = Theme.of(context).platform == TargetPlatform.iOS;