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快速参考

本页显示了若干 MongoDB 命令的驱动程序语法，以及指向相关引用和 API 文档的链接。

提示

使用 LINQ

您可以使用 LINQ 执行此页面上的许多操作。有关将 LINQ 与 .NET/C# 驱动程序一起使用的更多信息，请参阅 LINQ 基础知识页面。

命令

语法

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Name, "Bagels N Buns");
var restaurant = _restaurantsCollection.Find(filter).FirstOrDefault();
Console.WriteLine(restaurant);

{ name : "Bagels N Buns", restaurant_id : "40363427", ... }

查找文档（异步）

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Name, "Bagels N Buns");
var restaurant = await _restaurantsCollection.Find(filter).FirstOrDefaultAsync();
Console.WriteLine(restaurant);

{ name : "Bagels N Buns", restaurant_id : "40363427", ... }

查找多个文档

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(r => restaurant.Cuisine, "Pizza");
var restaurants = _restaurantsCollection.Find(filter).ToList();
Console.WriteLine(restaurants);

[
  { name: "Como Pizza", cuisine: "Pizza", ... },
  { name: "New York Pizza Suprema", cuisine: "Pizza", ... },
  ...
]

查找多个文档（异步）

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(r => restaurant.Cuisine, "Pizza");
var restaurants = await _restaurantsCollection.Find(filter).ToListAsync();
Console.WriteLine(restaurants);

[
  { name: "Como Pizza", cuisine: "Pizza", ... },
  { name: "New York Pizza Suprema", cuisine: "Pizza", ... },
  ...
]

插入文档

API 文档
 使用示例
 Fundamentals

var insertResult = _restaurantsCollection.InsertOne(new Restaurant { Name = "Mongo's Pizza" });

插入文档（异步）

API 文档
 使用示例
 Fundamentals

var insertResult = await _restaurantsCollection.InsertOneAsync(new Restaurant { Name = "Mongo's Pizza" });

插入多个文档

API 文档
 使用示例
 Fundamentals

_restaurantsCollection.InsertMany(new List<Restaurant>
{
    new Restaurant { Name = "Mongo's Pizza" },
    new Restaurant { Name = "Mongo Grill" }
});

插入多个文档（异步）

API 文档
 使用示例
 Fundamentals

await _restaurantsCollection.InsertManyAsync(new List<Restaurant>
{
    new Restaurant { Name = "Mongo's Pizza" },
    new Restaurant { Name = "Mongo Grill" }
});

更新文档

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Name, "Bagels N Buns");
var update = Builders<Restaurant>.Update
  .Set(restaurant => restaurant.Name, "2 Bagels 2 Buns");
var result = _restaurantsCollection.UpdateOne(filter, update);

更新文档（异步）

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Name, "Bagels N Buns");
var update = Builders<Restaurant>.Update
  .Set(restaurant => restaurant.Name, "2 Bagels 2 Buns");
var updateResult = await _restaurantsCollection.UpdateOneAsync(filter, update);

更新多个文档

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Pizza");
var update = Builders<Restaurant>.Update
  .Set(restaurant => restaurant.Cuisine, "Pasta and breadsticks");
var result = _restaurantsCollection.UpdateMany(filter, update);

更新多个文档（异步）

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Pizza");
var update = Builders<Restaurant>.Update
  .Set(restaurant => restaurant.Cuisine, "Pasta and breadsticks");
var updateResult = await _restaurantsCollection.UpdateManyAsync(filter, update);

更新文档中的数组

API 文档
 基础知识（更新一）
基础知识（更新多个）

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Name, "Bagels N Buns");
var update = Builders<Restaurant>.Update
  .Push(restaurant => restaurant.Grades, new GradeEntry
  {
    Date = DateTime.Now.ToUniversalTime(),
    Grade = "A",
    Score = 10
  });
var result = _restaurantsCollection.UpdateOne(filter, update);

替换文档

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Pizza");
// Find ID of first pizza restaurant
var oldPizzaRestaurant = _restaurantsCollection.Find(filter).First();
var oldId = oldPizzaRestaurant.Id;
Restaurant newPizzaRestaurant = new()
{
    Id = oldId,
    Name = "Mongo's Pizza",
    Cuisine = "Pizza",
    Address = new Address
    {
        Building = "123",
        Coordinates = [123, 456],
        Street = "Pizza St",
        ZipCode = "10003"
    },
    Borough = "Manhattan",
};
var replaceResult = _restaurantsCollection.ReplaceOne(filter, newPizzaRestaurant);

替换文档（异步）

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Pizza");
// Find ID of first pizza restaurant
var oldPizzaRestaurant = _restaurantsCollection.Find(filter).First();
var oldId = oldPizzaRestaurant.Id;
Restaurant newPizzaRestaurant = new()
{
    Id = oldId,
    Name = "Mongo's Pizza",
    Cuisine = "Pizza",
    Address = new Address
    {
        Building = "123",
        Coordinates = [12.3, 45.6],
        Street = "Pizza St",
        ZipCode = "10003"
    },
    Borough = "Manhattan",
};
var replaceResult = await _restaurantsCollection.ReplaceOneAsync(filter, newPizzaRestaurant);

删除文档

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Name, "Ready Penny Inn");
var deleteResult = _restaurantsCollection.DeleteOne(filter);

删除文档（异步）

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Name, "Ready Penny Inn");
var deleteResult = await _restaurantsCollection.DeleteOneAsync(filter);

删除多个文档

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Regex(restaurant => restaurant.Name, "Green");
var deleteResult = _restaurantsCollection.DeleteMany(filter);

删除多个文档（异步）

API 文档
 使用示例
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Regex(restaurant => restaurant.Name, "Green");
var deleteResult = await _restaurantsCollection.DeleteManyAsync(filter);

从游标迭代访问数据

API 文档

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Afghan)";
var cursor = _restaurantsCollection.Find(filter).ToCursor();
while (cursor.MoveNext())
{
    foreach (var r in cursor.Current)
    {
        Console.WriteLine(r.Name);
    }
}

[
  Afghan Kebab House
  Khyber Pass
  ...
]

计算文档

API 文档

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Pizza");
var count = _restaurantsCollection.Find(filter).CountDocuments();
Console.WriteLine(count);

列出不同的文档或字段值

API 文档

var filter = Builders<Restaurant>.Filter.Empty;
var restaurants = _restaurantsCollection
  .Distinct(r => r.Cuisine, filter);
Console.WriteLine(restaurants);

[ Afghan, African, American, Armenian, Asian, ... ]

限制检索的文档数量

API 文档

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Asian");
var restaurants = _restaurantsCollection.Find(filter).Limit(3).ToList();
Console.WriteLine(restaurants);

[
  { name: "China Grill", ... },
  { name: "Indo Chine", ... },
  { name: "Le Colonial", ... }
]

跳过检索到的文档

API 文档

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Asian");
var restaurants = _restaurantsCollection.Find(filter).Skip(2).ToList();
Console.WriteLine(restaurants);

[
  { name: "Le Colonial", ... },
  { name: "Citrus Bar & Grill", ... },
  { name: "Mangez Avec Moi", ... },
  ...
]

检索文档时对文档进行排序

API 文档

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Brazilian");
var restaurants =  _restaurantsCollection.Find(filter)
  .SortBy(r => r.Name).ToList();
Console.WriteLine(restaurants);

[
  { name: "Barzinho", ... },
  { name: "Beco", ... },
  { name: "Beija-Flor", ... },
  ...
]

检索项目文档字段时

API 文档
 Fundamentals

var filter = Builders<Restaurant>.Filter
  .Eq(restaurant => restaurant.Cuisine, "Italian");
var projection = Builders<Restaurant>.Projection
  .Include(restaurant => restaurant.Name)
  .Include(restaurant => restaurant.Borough)
  .Exclude(restaurant => restaurant.Id);
var restaurants = _restaurantsCollection.Find(filter).Project(projection).ToList();
Console.WriteLine(restaurants);

[
  { borough : "Brooklyn", name : "Philadelphia Grille Express" }
  { borough : "Manhattan", name : "Isle Of Capri Restaurant" }
  { borough : "Manhattan", name : "Marchis Restaurant" }
  ...
]

创建索引

API 文档
 Fundamentals

var index = Builders<Restaurant>.IndexKeys
  .Ascending(restaurant => restaurant.Cuisine);
_restaurantsCollection.Indexes
  .CreateOne(new CreateIndexModel<Restaurant>(index));