Adding BSON array to BsonDocument in MongoDB

Question

How can I add BsonArray to BsonDocument in MongoDB using a C# driver? I want a result something like this

{ 
    author: 'joe',
    title : 'Yet another blog post',
    text : 'Here is the text...',
    tags : [ 'example', 'joe' ],
    comments : [ { author: 'jim', comment: 'I disagree' },
                 { author: 'nancy', comment: 'Good post' }
    ]
}

Can you please clarify you question. What are you trying to do? Create above described document thorugh BsonDocument? Or you trying to add comment to existing author? Mb your show code.. — Andrew Orsich, Jun 07 '11 at 06:28

score 32 · Answer 1 · edited Dec 27 '20 at 21:20

32

You can create the above document in C# with the following statement:

var document = new BsonDocument {
    { "author", "joe" },
    { "title", "yet another blog post" },
    { "text", "here is the text..." },
    { "tags", new BsonArray { "example", "joe" } },
    { "comments", new BsonArray {
        new BsonDocument { { "author", "jim" }, { "comment", "I disagree" } },
        new BsonDocument { { "author", "nancy" }, { "comment", "Good post" } }
    }}
};

You can test whether you produced the correct result with:

var json = document.ToJson();

edited Dec 27 '20 at 21:20

derekbaker783

8,109
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answered Jun 08 '11 at 03:54

Robert Stam

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1

I'd also add that any null values are ignored by default. – Razor Jun 08 '11 at 04:08
how to handle with { "$concat":[ {"$toString": 1}, '2', {"$toString":3} ]} ? – Panic Apr 07 '21 at 08:40

score 11 · Answer 2 · answered Oct 26 '13 at 09:26

you can also add the array after the BsonDocument already exists, like this:

BsonDocument  doc = new BsonDocument {
    { "author", "joe" },
        { "title", "yet another blog post" },
     { "text", "here is the text..." }
};

BsonArray  array1 = new BsonArray {
        "example", "joe"
    };


BsonArray  array2 = new BsonArray {
        new BsonDocument { { "author", "jim" }, { "comment", "I disagree" } },
        new BsonDocument { { "author", "nancy" }, { "comment", "Good post" } }
    };


doc.Add("tags", array1);
doc.Add("comments", array2);

helped on how to create a bson array without having a bsondocument inside. — vishnu viswanath, Jan 30 '14 at 12:40

Adding BSON array to BsonDocument in MongoDB

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