• 4.0 MongoDB基础-增删改查


    查询

    先向数据库中插入几条数据

    var documents = new BsonDocument[]
    {
        new BsonDocument
        {
            { "item", "journal" },
            { "qty", 25 },
            { "size", new BsonDocument { { "h", 14 }, { "w", 21 }, {  "uom", "cm"} } },
            { "status", "A" }
        },
        new BsonDocument
        {
            { "item", "notebook" },
            { "qty", 50 },
            { "size", new BsonDocument { { "h",  8.5 }, { "w", 11 }, {  "uom", "in"} } },
            { "status", "A" }
        },
        new BsonDocument
        {
            { "item", "paper" },
            { "qty", 100 },
            { "size", new BsonDocument { { "h",  8.5 }, { "w", 11 }, {  "uom", "in"} } },
            { "status", "D" }
        },
        new BsonDocument
        {
            { "item", "planner" },
            { "qty", 75 },
            { "size", new BsonDocument { { "h", 22.85 }, { "w", 30  }, {  "uom", "cm"} } },
            { "status", "D" }
        },
        new BsonDocument
        {
            { "item", "postcard" },
            { "qty", 45 },
            { "size", new BsonDocument { { "h", 10 }, { "w", 15.25 }, {  "uom", "cm"} } },
            { "status", "A" }
        },
    };
    collection.InsertMany(documents);
    
    

    查询全部结果

    var filter = Builders<BsonDocument>.Filter.Empty;
    var result = collection.Find(filter).ToList();
    

    查询等于条件

    //语法
    Builders<BsonDocument>.Filter.Eq(<field>, <value>);
    //实例
    var filter = Builders<BsonDocument>.Filter.Eq("status", "D");
    var result = collection.Find(filter).ToList();

    指定的查询条件

    //语法
    var builder = Builders<BsonDocument>.Filter;
    builder.And(builder.Eq(<field1>, <value1>), builder.Lt(<field2>, <value2>));
    //实例
    var filter = Builders<BsonDocument>.Filter.In("status", new[] { "A", "D" });
    var result = collection.Find(filter).ToList();

    指定And条件

    var builder = Builders<BsonDocument>.Filter;
    var filter = builder.And(builder.Eq("status", "A"), builder.Lt("qty", 30));
    var result = collection.Find(filter).ToList();

    指定 Or 条件

    var builder = Builders<BsonDocument>.Filter;
    var filter = builder.Or(builder.Eq("status", "A"), builder.Lt("qty", 30));
    var result = collection.Find(filter).ToList();

    指定 And 也指定 Or条件

    var builder = Builders<BsonDocument>.Filter;
    var filter = builder.And(
        builder.Eq("status", "A"),
        builder.Or(builder.Lt("qty", 30), builder.Regex("item", new BsonRegularExpression("^p"))));
    var result = collection.Find(filter).ToList();
    

    增删改查的地址:

    https://docs.mongodb.com/guides/server/insert/

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  • 原文地址:https://www.cnblogs.com/maanshancss/p/12978140.html
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