前言

很简单的一个 zip 包解压缩的功能但是 windows 平台中文显示乱码很糟心搜了一圈没找到现成的方法在此贴上我的解决方式。

实现

导入需要的包

flutter pub add archive

flutter pub add fast_gbk

flutter pub add path

代码如下

import 'dart:io';
import 'package:fast_gbk/fast_gbk.dart';
import 'package:archive/archive.dart';
import 'package:path/path.dart' as p;

void main() {
  unzip('G:/testUpdate/111.zip', 'G:/testUpdate/1');
}

void unzip(String inputPath, String outputPath) {
  var archive = zipDecode(inputPath);

  for (final file in archive) {
    final filename = file.name;
    final filePath = p.join(outputPath, filename);

    if (!file.isFile && !file.isSymbolicLink) {
      Directory(filePath).createSync(recursive: true);
      continue;
    }

    if (file.isSymbolicLink) {
      final link = Link(filePath);
      link.createSync(p.normalize(file.nameOfLinkedFile), recursive: true);
    } else {
      final data = file.content as List<int>;
      final newFile = File(filePath);
      newFile.createSync(recursive: true);
      newFile.writeAsBytesSync(data);
    }
  }
}

// 由于 archive 包直接用会乱码这里加一下对于 gbk 编码的处理
Archive zipDecode(String inputPath) {
  final zipFile = File(inputPath);
  final bytes = zipFile.readAsBytesSync();
  final inputStream = InputStream(bytes);
  // final inputStream = InputFileStream('G:/testUpdate/111.zip');
  var directory = ZipDirectory.read(inputStream);

  final archive = Archive();

  for (final zfh in directory.fileHeaders) {
    final zf = zfh.file!;

    // The attributes are stored in base 8
    final mode = zfh.externalFileAttributes!;
    final compress = zf.compressionMethod != ZipFile.STORE;

    //dynamic content = zf.rawContent;
    var file = ArchiveFile(
        zf.filename, zf.uncompressedSize!, zf, zf.compressionMethod);

    file.mode = mode >> 16;

    // see https://github.com/brendan-duncan/archive/issues/21
    // UNIX systems has a creator version of 3 decimal at 1 byte offset
    if (zfh.versionMadeBy >> 8 == 3) {
      file.isFile = false;

      final fileType = file.mode & 0xF000;
      switch (fileType) {
        case 0x8000:
        case 0x0000: // No determination can be made so we assume it's a file.
          file.isFile = true;
          break;
        case 0xA000:
          file.isSymbolicLink = true;
          break;
        default:
      }
    } else {
      file.isFile = !file.name.endsWith('/');
    }

    file.crc32 = zf.crc32;
    file.compress = compress;
    file.lastModTime = zf.lastModFileDate << 16 | zf.lastModFileTime;

    final needGbkDecode = zf.flags & 2048 == 0;
    if (needGbkDecode) {
      file.name = gbk.decode(zf.filename.codeUnits);
    }

    archive.addFile(file);
  }

  return archive;
}

昨天刚接触的 flutter若是代码有问题还望指出非常感谢