/// <summary>
/// 针对大文件 chunk的帮助类
/// 不经常使用所以没有静态
/// MongoDB 版本4.2
/// 参考网址
/// https://docs.mongodb.com/manual/tutorial/query-documents/
/// https://www.runoob.com/mongodb/mongodb-tutorial.html
/// </summary>
public class GridFSHelper
{
private ObjectId oid;
private readonly GridFSBucket bucket;
private GridFSFileInfo fileInfo;
private readonly IMongoCollection<BsonDocument> collection;
/// <summary>
/// 初始化数据库连接信息
/// </summary>
/// <param name="host">MongoDB连接信息,实例(链接字符串,数据库,[表])</param>
public GridFSHelper(MongodbHostOptions host)
{
MongoClient client = new MongoClient(host.Connection);
IMongoDatabase mongoDatabase = client.GetDatabase(host.DataBase);
// 这里定义了默认的表名称 这里应该把"my_bucket.files" 设置为参数
collection = mongoDatabase.GetCollection<BsonDocument>(host.CollectionName + ".files");
bucket = new GridFSBucket(mongoDatabase, new GridFSBucketOptions
{
BucketName = host.CollectionName,
ChunkSizeBytes = 1048576 //每个大文件被分割的块大小
});
}
/// <summary>
/// 上传文件
///
///
/// </summary>
/// <param name="gfsname"></param>
/// <param name="source"></param>
/// <param name="filename"></param>
/// <returns></returns>
public async Task<ObjectId> UploadFromStreamAsync(string gfsname, Stream source, string filename)
{
var options = new GridFSUploadOptions
{
Metadata = new BsonDocument {
{ "filename", filename },
{ "contentType",Path.GetDirectoryName(filename)}
},
};
return await bucket.UploadFromStreamAsync(gfsname, source, options);
}
/// <summary>
/// GridFS 上传图片 图片不是特别大的时候 这个时候是上传到内存当中
/// </summary>
/// <param name="host"></param>
/// <param name="entity"></param>
/// <returns></returns>
public async Task<ObjectId> AddAsync(Images_Mes imagesMes)
{
var options = new GridFSUploadOptions
{
Metadata = new BsonDocument
{
{ "filename", imagesMes.FileName },
{ "contentType",imagesMes.FileType}
},
DisableMD5 = true,
};
ObjectId objectId = await bucket.UploadFromBytesAsync(imagesMes.FileName, imagesMes.ByteImg, options);
return objectId;
}
/// <summary>
/// FS 查询图片
/// </summary>
/// <param name="id">Objectid 主键</param>
/// <returns></returns>
public async Task<Images_Mes> DownSync(ObjectId id)
{
Images_Mes imagesMes = new Images_Mes();
byte[] byteImg = await bucket.DownloadAsBytesAsync(id);
imagesMes.ByteImg = byteImg;
var filter = Builders<BsonDocument>.Filter.Eq("_id", id);
var doucument = collection.FindAsync(filter).GetAwaiter().GetResult();
var test = doucument.ToList().First();
//Console.WriteLine(test.GetValue("filename"));
imagesMes.FileName = test.GetValue("filename")?.ToString();
return imagesMes;
}
//修改图片 对文档重新命名
public async Task RenameSync(ObjectId id, string NewName)
{
await bucket.RenameAsync(id, NewName);
}
/// <summary>
/// 删除图片
/// </summary>
/// <param name="id">Objectid 主键</param>
/// <returns></returns>
public async Task DeleteSync(ObjectId id)
{
try
{
await bucket.DeleteAsync(id);
}
catch (Exception e)
{
Console.WriteLine(e);
}
}
/// <summary>
/// 删除多个图片
/// </summary>
/// <param name="idlist"></param>
/// <returns></returns>
public async Task DeleteListSync(List<ObjectId> idlist)
{
foreach (var id in idlist)
{
await bucket.DeleteAsync(id);
}
}
public ObjectId UploadGridFSFromBytes(string filename, Byte[] source)
{
oid = bucket.UploadFromBytes(filename, source);
return oid;
}
public ObjectId UploadGridFSFromStream(string filename, Stream source)
{
using (source)
{
oid = bucket.UploadFromStream(filename, source);
return oid;
}
}
public Byte[] DownloadAsByteArray(ObjectId id)
{
Byte[] bytes = bucket.DownloadAsBytes(id);
return bytes;
}
public Stream DownloadToStream(ObjectId id)
{
Stream destination = new MemoryStream();
bucket.DownloadToStream(id, destination);
return destination;
}
public Byte[] DownloadAsBytesByName(string filename)
{
Byte[] bytes = bucket.DownloadAsBytesByName(filename);
return bytes;
}
public Stream DownloadToStreamByName(string filename)
{
Stream destination = new MemoryStream();
bucket.DownloadToStreamByName(filename, destination);
return destination;
}
public GridFSFileInfo FindFiles(string filename)
{
var filter = Builders<GridFSFileInfo>.Filter.And(
Builders<GridFSFileInfo>.Filter.Eq(x => x.Filename, "man"),
Builders<GridFSFileInfo>.Filter.Gte(x => x.UploadDateTime, new DateTime(2015, 1, 1, 0, 0, 0, DateTimeKind.Utc)),
Builders<GridFSFileInfo>.Filter.Lt(x => x.UploadDateTime, new DateTime(2017, 2, 1, 0, 0, 0, DateTimeKind.Utc)));
var sort = Builders<GridFSFileInfo>.Sort.Descending(x => x.UploadDateTime);
var options = new GridFSFindOptions
{
Limit = 1,
Sort = sort
};
using (var cursor = bucket.Find(filter, options))
{
fileInfo = cursor.ToList().FirstOrDefault();
}
return fileInfo;
}
public void DeleteAndRename(ObjectId id)
{
bucket.Delete(id);
}
//The “fs.files” collection will be dropped first, followed by the “fs.chunks” collection. This is the fastest way to delete all files stored in a GridFS bucket at once.
public void DroppGridFSBucket()
{
bucket.Drop();
}
public void RenameAsingleFile(ObjectId id, string newFilename)
{
bucket.Rename(id, newFilename);
}
public void RenameAllRevisionsOfAfile(string oldFilename, string newFilename)
{
var filter = Builders<GridFSFileInfo>.Filter.Eq(x => x.Filename, oldFilename);
var filesCursor = bucket.Find(filter);
var files = filesCursor.ToList();
foreach (var file in files)
{
bucket.Rename(file.Id, newFilename);
}
}
}