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import mediaLibrary from '@ohos.multimedia.mediaLibrary';

const context = getContext(this);
var media = mediaLibrary.getMediaLibrary(context);
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{
  "module": {
    "requestPermissions": [
      {
        "name": "ohos.permission.MEDIA_LOCATION",
        "reason": "$string:reason",
        "usedScene": {
          "abilities": [
            "EntryAbility"
          ],
          "when": "always"
        }
      },
      {
        "name": "ohos.permission.READ_MEDIA",
        "reason": "$string:reason",
        "usedScene": {
          "abilities": [
            "EntryAbility"
          ],
          "when": "always"
        }
      },
      {
        "name": "ohos.permission.WRITE_MEDIA",
        "reason": "$string:reason",
        "usedScene": {
          "abilities": [
            "EntryAbility"
          ],
          "when": "always"
        }
      }
    ]
  }
}    
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import UIAbility from '@ohos.app.ability.UIAbility';
import abilityAccessCtrl, {Permissions} from '@ohos.abilityAccessCtrl';

export default class EntryAbility extends UIAbility {
  onWindowStageCreate(windowStage) {
    let list : Array<Permissions> = ['ohos.permission.READ_MEDIA', 'ohos.permission.WRITE_MEDIA'];
    let permissionRequestResult;
    let atManager = abilityAccessCtrl.createAtManager();
    atManager.requestPermissionsFromUser(this.context, list, (err, result) => {
      if (err) {
        console.error('requestPermissionsFromUserError: ' + JSON.stringify(err));
      } else {
        permissionRequestResult = result;
        console.info('permissionRequestResult: ' + JSON.stringify(permissionRequestResult));
      }
    });       
  }
}
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async function example() {
  let fileKeyObj = mediaLibrary.FileKey;
  let fileType = mediaLibrary.MediaType.IMAGE;
  let option = {
    selections: fileKeyObj.MEDIA_TYPE + '= ?',
    selectionArgs: [fileType.toString()],
  };
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const fetchFileResult = await media.getFileAssets(option);
  fetchFileResult.getFirstObject().then((fileAsset) => {
    console.log('getFirstObject.displayName : ' + fileAsset.displayName);
    for (let i = 1; i < fetchFileResult.getCount(); i++) {
      fetchFileResult.getNextObject().then((fileAsset) => {
        console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
      }).catch((err) => {
        console.error('Failed to get next object: ' + err);
      });
    }
  }).catch((err) => {
    console.error('Failed to get first object: ' + err);
  });
}
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async function example() {
  let fileKeyObj = mediaLibrary.FileKey;
  let option = {
    selections: fileKeyObj.DATE_ADDED + '> ?',
    selectionArgs: ['2022-8-5'],
  };
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const fetchFileResult = await media.getFileAssets(option);
  fetchFileResult.getFirstObject().then((fileAsset) => {
    console.info('getFirstObject.displayName : ' + fileAsset.displayName);
    for (let i = 1; i < fetchFileResult.getCount(); i++) {
      fetchFileResult.getNextObject().then((fileAsset) => {
        console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
      }).catch((err) => {
        console.error('Failed to get next object: ' + err);
      });
    }
  }).catch((err) => {
    console.error('Failed to get first object: ' + err);
  });
}
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async function example() {
  let fileKeyObj = mediaLibrary.FileKey;
  let fileType = mediaLibrary.MediaType.IMAGE;
  let option = {
    selections: fileKeyObj.MEDIA_TYPE + '= ?',
    selectionArgs: [fileType.toString()],
    order: fileKeyObj.DATE_ADDED + " DESC",
  };
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const fetchFileResult = await media.getFileAssets(option);
  fetchFileResult.getFirstObject().then((fileAsset) => {
    console.info('getFirstObject.displayName : ' + fileAsset.displayName);
    for (let i = 1; i < fetchFileResult.getCount(); i++) {
      fetchFileResult.getNextObject().then((fileAsset) => {
        console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
      }).catch((err) => {
        console.error('Failed to get next object: ' + err);
      });
    }
  }).catch((err) => {
    console.error('Failed to get first object: ' + err);
  });
}
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async function example() {
  let fileKeyObj = mediaLibrary.FileKey;
  let option = {
    selections: fileKeyObj.ALBUM_NAME + '= ?',
    selectionArgs: ['myAlbum'],
  };
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const fetchFileResult = await media.getFileAssets(option);
  if (albumList.length > 0) {
    fetchFileResult.getFirstObject().then((album) => {
      console.info('getFirstObject.displayName : ' + album.albumName);
    }).catch((err) => {
      console.error('Failed to get first object: ' + err);
    });
  } else {
    console.info('getAlbum list is: 0');
  }
}
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let fileKeyObj = mediaLibrary.FileKey;
let AlbumNoArgsFetchOp = {
  selections: fileKeyObj.ALBUM_NAME + '= ?',
  selectionArgs: ['新建相册1']
}
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let fileKeyObj = mediaLibrary.FileKey;
let videoType = mediaLibrary.MediaType.VIDEO;
let videoFetchOp  = {
  selections: fileKeyObj.MEDIA_TYPE + '= ?',
  selectionArgs: [videoType.toString()],
}
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async function getCameraImagePromise() {
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  let fileKeyObj = mediaLibrary.FileKey;
  let videoType = mediaLibrary.MediaType.VIDEO;
  let videoFetchOp = {
    selections: fileKeyObj.MEDIA_TYPE + '= ?',
    selectionArgs: [videoType.toString()],
  }
  let AlbumNoArgsFetchOp = {
    selections: fileKeyObj.ALBUM_NAME + '= ?',
    selectionArgs: ['新建相册1']
  }

  let albumList = await media.getAlbums(AlbumNoArgsFetchOp);
  if (albumList.length > 0) {
    const album = albumList[0];
    let fetchFileResult = await album.getFileAssets(videoFetchOp);
    let count = fetchFileResult.getCount();
    console.info("get mediaLibrary VIDEO number", count);
  } else {
    console.info('getAlbum list is: 0');
  }
}
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async function getFirstThumbnailPromise() {
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  let fileKeyObj = mediaLibrary.FileKey;
  let imageType = mediaLibrary.MediaType.IMAGE;
  let imagesFetchOp = {
    selections: fileKeyObj.MEDIA_TYPE + '= ?',
    selectionArgs: [imageType.toString()],
  }

  let size = { width: 720, height: 720 };
  const fetchFileResult = await media.getFileAssets(imagesFetchOp);
  if (fetchFileResult === undefined) {
    console.error("get image failed with error");
    return;
  } else {
    const asset = await fetchFileResult.getFirstObject();
    asset.getThumbnail(size).then((pixelMap) => {
      pixelMap.getImageInfo().then((info) => {
        console.info('get Thumbnail info: ' + "width: " + info.size.width + " height: " + info.size.height);
      }).catch((err) => {
        console.error("getImageInfo failed with error: " + err);
      });
    }).catch((err) => {
      console.error("getImageInfo failed with error: " + err);
    });
  }
}
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async function example() {
  let mediaType = mediaLibrary.MediaType.FILE;
  let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const path = await media.getPublicDirectory(DIR_DOCUMENTS);
  media.createAsset(mediaType, "testFile.text", path).then((asset) => {
    console.info("createAsset successfully:"+ JSON.stringify(asset));
  }).catch((err) => {
    console.error("createAsset failed with error: " + err);
  });
}
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async function example() {
  let fileKeyObj = mediaLibrary.FileKey;
  let fileType = mediaLibrary.MediaType.FILE;
  let option = {
    selections: fileKeyObj.MEDIA_TYPE + '= ?',
    selectionArgs: [fileType.toString()],
  };
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const fetchFileResult = await media.getFileAssets(option);
  let asset = await fetchFileResult.getFirstObject();
  if (asset === undefined) {
    console.error('asset not exist');
    return;
  }
  //回调为空
  asset.trash(true).then(() => {
    console.info("trash successfully");
  }).catch((err) => {
    console.error("trash failed with error: " + err);
  });
}
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async function example() {
  let fileKeyObj = mediaLibrary.FileKey;
  let fileType = mediaLibrary.MediaType.IMAGE;
  let option = {
    selections: fileKeyObj.MEDIA_TYPE + '= ?',
    selectionArgs: [fileType.toString()],
  };
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const fetchFileResult = await media.getFileAssets(option);
  let asset = await fetchFileResult.getFirstObject();
  if (asset === undefined) {
    console.error('asset not exist');
    return;
  }
  asset.displayName = 'newImage.jpg';
  //回调为空
  asset.commitModify((err) => {
    if (err) {
      console.error('fileRename Failed ');
      return;
    }
    console.info('fileRename successful.');
  });
}
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async function example(){
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  let DIR_CAMERA = mediaLibrary.DirectoryType.DIR_CAMERA;
  const dicResult = await media.getPublicDirectory(DIR_CAMERA);
  if (dicResult == 'Camera/') {
    console.info('mediaLibraryTest : getPublicDirectory passed');
  } else {
    console.error('mediaLibraryTest : getPublicDirectory failed');
  }
}
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async function copyPublic2Sandbox() {
  try {
    const context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let sandboxDirPath = context.filesDir;
    let fileKeyObj = mediaLibrary.FileKey;
    let fileAssetFetchOp = {
      selections: fileKeyObj.DISPLAY_NAME + '= ?',
      selectionArgs: ['testFile.txt'],
    };
    let fetchResult = await media.getFileAssets(fileAssetFetchOp);
    let fileAsset = await fetchResult.getFirstObject();

    let fdPub = await fileAsset.open('rw');
    let fdSand = await fs.open(sandboxDirPath + '/testFile.txt', fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE);
    await fs.copyFile(fdPub, fdSand.fd);

    await fileAsset.close(fdPub);
    await fs.close(fdSand.fd);

    let content_sand = await fs.readText(sandboxDirPath + '/testFile.txt');
    console.info('content read from sandbox file: ', content_sand)
  } catch (err) {
    console.info('[demo] copyPublic2Sandbox fail, err: ', err);
  }
}
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async function copySandbox2Public() {
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  let sandboxDirPath = context.filesDir;

  let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
  const publicDirPath = await media.getPublicDirectory(DIR_DOCUMENTS);
  try {
    let fileAsset = await media.createAsset(mediaLibrary.MediaType.FILE, 'testFile02.txt', publicDirPath);
    console.info('createFile successfully, message = ' + fileAsset);
  } catch (err) {
    console.error('createFile failed, message = ' + err);
  }
  try {
    let fileKeyObj = mediaLibrary.FileKey;
    let fileAssetFetchOp = {
      selections: fileKeyObj.DISPLAY_NAME + '= ?',
      selectionArgs: ['testFile02.txt'],
    };
    let fetchResult = await media.getFileAssets(fileAssetFetchOp);
    var fileAsset = await fetchResult.getFirstObject();
  } catch (err) {
    console.error('file asset get failed, message = ' + err);
  }
  let fdPub = await fileAsset.open('rw');
  let fdSand = await fs.open(sandboxDirPath + 'testFile.txt', fs.OpenMode.READ_WRITE);
  await fs.copyFile(fdSand.fd, fdPub);
  await fileAsset.close(fdPub);
  await fs.close(fdSand.fd);
  let fdPubRead = await fileAsset.open('rw');
  try {
    let arrayBuffer = new ArrayBuffer(4096);
    await fs.read(fdPubRead, arrayBuffer);
    var content_pub = String.fromCharCode(...new Uint8Array(arrayBuffer));
    fileAsset.close(fdPubRead);
  } catch (err) {
    console.error('read text failed, message = ', err);
  }
  console.info('content read from public file: ', content_pub);
}
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async function example() {
  let mediaType = mediaLibrary.MediaType.FILE;
  let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const path = await media.getPublicDirectory(DIR_DOCUMENTS);
  media.createAsset(mediaType, "testFile.text", path).then((asset) => {
    console.info("createAsset successfully:" + JSON.stringify(asset));
  }).catch((err) => {
    console.error("createAsset failed with error: " + err);
  });
}
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async function writeOnlyPromise() {
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  let fileKeyObj = mediaLibrary.FileKey;
  let fileAssetFetchOp = {
    selections: fileKeyObj.DISPLAY_NAME + '= ?',
    selectionArgs: ['testFile.txt'],
  };
  let fetchResult = await media.getFileAssets(fileAssetFetchOp);
  let fileAsset = await fetchResult.getFirstObject();
  console.info('fileAssetName: ', fileAsset.displayName);

  try {
    let fd = await fileAsset.open('w');
    console.info('file descriptor: ', fd);
    await fs.write(fd, "Write file test content.");
    await fileAsset.close(fd);
  } catch (err) {
    console.error('write file failed, message = ', err);
  }
}
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async function readOnlyPromise() {
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  let fileKeyObj = mediaLibrary.FileKey;
  let fileAssetFetchOp = {
    selections: fileKeyObj.DISPLAY_NAME + '= ?' ,
    selectionArgs: ['testFile.txt'],
  };
  let fetchResult = await media.getFileAssets(fileAssetFetchOp);
  let fileAsset = await fetchResult.getFirstObject();
  console.info('fileAssetName: ', fileAsset.displayName);

  try {
    let fd = await fileAsset.open('r');
    let arrayBuffer = new ArrayBuffer(4096);
    await fs.read(fd, arrayBuffer);
    let fileContent = String.fromCharCode(...new Uint8Array(arrayBuffer));
    globalThis.fileContent = fileContent;
    globalThis.fileName = fileAsset.displayName;
    console.info('file content: ', fileContent);
    await fileAsset.close(fd);
  } catch (err) {
    console.error('read file failed, message = ', err);
  }
}
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async function example() {
  let mediaType = mediaLibrary.MediaType.IMAGE;
  let DIR_IMAGE = mediaLibrary.DirectoryType.DIR_IMAGE;
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  const path = await media.getPublicDirectory(DIR_IMAGE);
  //myAlbum为新建文件保存路径，也是新建相册的名称
  media.createAsset(mediaType, 'test.jpg', path + 'myAlbum/', (err, fileAsset) => {
    if (fileAsset === undefined) {
      console.error('createAlbum failed, message = ' + err);
    } else {
      console.info('createAlbum successfully, message = ' + JSON.stringify(fileAsset));
    }
  });
}
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async function example() {
  let AlbumNoArgsfetchOp = {
    selections: '',
    selectionArgs: [],
  };
  const context = getContext(this);
  let media = mediaLibrary.getMediaLibrary(context);
  let albumList = await media.getAlbums(AlbumNoArgsfetchOp);
  let album = albumList[0];
  album.albumName = 'newAlbum';
  //回调返回空
  album.commitModify().then(() => {
    console.info("albumRename successfully");
  }).catch((err) => {
    console.error("albumRename failed with error: " + err);
  });
}
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