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来源： MongoDB for .Net Core 查询条件之 Builders类 – hahaMan – 博客园
使用MongoDB有段时间了 今天终于有用总结下
UpdateDefinitionBuilder，SortDefinitionBuilder，ProjectionDefinitionBuilder，IndexKeysDefinitionBuilder，FilterDefinitionBuilder应用
Builders
//
// 摘要:
// A static helper class containing various builders.
//
// 类型参数:
// TDocument:
// The type of the document.
public static class Builders<TDocument>
{
//
// 摘要:
// Gets a MongoDB.Driver.FilterDefinitionBuilder`1.
public static FilterDefinitionBuilder<TDocument> Filter { get; }
//
// 摘要:
// Gets an MongoDB.Driver.IndexKeysDefinitionBuilder`1.
public static IndexKeysDefinitionBuilder<TDocument> IndexKeys { get; }
//
// 摘要:
// Gets a MongoDB.Driver.ProjectionDefinitionBuilder`1.
public static ProjectionDefinitionBuilder<TDocument> Projection { get; }
//
// 摘要:
// Gets a MongoDB.Driver.SortDefinitionBuilder`1.
public static SortDefinitionBuilder<TDocument> Sort { get; }
//
// 摘要:
// Gets an MongoDB.Driver.UpdateDefinitionBuilder`1.
public static UpdateDefinitionBuilder<TDocument> Update { get; }
}
案例：
FilterDefinitionBuilder这个一般用作查询条件
var builderlist = new List<FilterDefinition<BsonDocument>>();
builderlist.Add(Builders<BsonDocument>.Filter.Gte("EndTime", DateTime.UtcNow));
builderlist.Add(Builders<BsonDocument>.Filter.Eq("Type", BanType.Freeze));
builderlist.Add(Builders<BsonDocument>.Filter.Eq("RoleId", form.RoleId));
var filter = Builders<BsonDocument>.Filter.And(builderlist);
//同步
_mongoDbContext.Collection<BsonDocument>().Find(filter).SortByDescending(n => n.EndTime).ToList();
//异步
await _mongoDbContext.Collection<BsonDocument>().Find(filter).SortByDescending(n => n.EndTime).ToListAsync();
UpdateDefinitionBuilder 此类用在修改数据的时候
FilterDefinition<BsonDocument> filter = Builders<BsonDocument>.Filter.Eq("_id", id);
var list = new List<UpdateDefinition<BsonDocument>>();
list.Add(Builders<BsonDocument>.Update.Set("EndTime", DateTime.UtcNow.AddDays(day)));
list.Add(Builders<BsonDocument>.Update.Set("Operator", new UserSnapshot { Id = UserId, Name = UserName }));
list.Add(Builders<BsonDocument>.Update.Set("Remark", Remark));
list.Add(Builders<BsonDocument>.Update.Set("Category", Category));
var setfilter = Builders<BsonDocument>.Update.Combine(list);
//同步调用
_mongoDbContext.Collection<BsonDocument>().UpdateOne(filter , setfilter);
//异步调用
await _mongoDbContext.Collection<BsonDocument>().UpdateOneAsync(filter , setfilter);
ProjectionDefinitionBuilder 查询指定的值
//创建约束生成器
FilterDefinitionBuilder<BsonDocument> builderFilter = Builders<BsonDocument>.Filter;
ProjectionDefinitionBuilder<BsonDocument> builderProjection = Builders<BsonDocument>.Projection;
//Include 包含某元素 Exclude 不包含某元素
ProjectionDefinition<BsonDocument> projection = builderProjection.Include("RoleId");
var list = await _mongoDbContext.Collection<BsonDocument>().Find(builderFilter.Empty).Project(projection).ToListAsync();
//创建约束生成器
FilterDefinitionBuilder<BsonDocument> builderFilter = Builders<BsonDocument>.Filter;
ProjectionDefinitionBuilder<BsonDocument> builderProjection = Builders<BsonDocument>.Projection;
//Include 包含某元素 Exclude 不包含某元素
ProjectionDefinition<BsonDocument> projection = builderProjection.Exclude("RoleId");
_mongoDbContext.Collection<BsonDocument>().Find(builderFilter.Empty).Project(projection).ToListAsync();
SortDefinitionBuilder 排序
FilterDefinitionBuilder<BsonDocument> builderFilter = Builders<BsonDocument>.Filter;
SortDefinitionBuilder<BsonDocument> builderSort = Builders<BsonDocument>.Sort;
//排序约束 Ascending 正序 Descending 倒序
SortDefinition<BsonDocument> sort = builderSort.Ascending("RoleId");
SortDefinition<BsonDocument> sort2 = builderSort.Descending("RoleId");
var list = await _mongoDbContext.Collection<BsonDocument>().Find(builderFilter.Empty).Sort(sort).ToListAsync();
