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MongoDB: build query in c # driver

I compiled this Mongodb request in the C # driver:

{ 
    Location: { "$within": { "$center": [ [1, 1], 5 ] } },
    Properties: {
        $all: [
            { $elemMatch: { Type: 1, Value: "a" } },
            { $elemMatch: { Type: 2, Value: "b" } }
        ]
    }
}

Something as follows:

var geoQuery = Query.WithinCircle("Location", x, y, radius);
var propertiesQuery = **?**;
var query = Query.And(geoQuery, propertiesQuery);

Addition:

The above query, taken from my other question: MongoDB: matching multiple array elements You can take part in its solution.

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2 answers

Here, as if you would like to receive this exact request:

// create the $elemMatch with Type and Value
// as we're just trying to make an expression here, 
// we'll use $elemMatch as the property name 
var qType1 = Query.EQ("$elemMatch", 
    BsonValue.Create(Query.And(Query.EQ("Type", 1),
                     Query.EQ("Value", "a"))));
// again
var qType2 = Query.EQ("$elemMatch", 
    BsonValue.Create(Query.And(Query.EQ("Type", 2), 
                     Query.EQ("Value", "b"))));
// then, put it all together, with $all connection the two queries 
// for the Properties field
var query = Query.All("Properties", 
    new List<BsonValue> { 
        BsonValue.Create(qType1), 
        BsonValue.Create(qType2)
    });

The routine is that although many parameters for various methods Queryare expected BsonValueinstead of queries, you can create an instance BsonValuefrom the instance Queryby doing something like:

// very cool/handy that this works
var bv = BsonValue.Create(Query.EQ("Type", 1));

The actual request sent exactly matches your original request:

query = {
  "Properties": {
    "$all": [ 
        { "$elemMatch": { "Type": 1, "Value": "a" }}, 
        { "$elemMatch": { "Type": 2, "Value": "b" }}
    ]
  }
}

( $all, , -, = "/questions/478816/multiple-elemmatch-expressions-for-matching-array-values-using-all-in-mongodb" > ).

+5

, , $all, , , , :

Syntax: { field: { $all: [ <value> , <value1> ... ] }

( <expression>, , $and). , # BsonValue IMongoQuery.

:

{
    $and: [
        { "Location": { "$within": { "$center": [ [1, 1], 5 ] } } },
        { "Properties" : { $elemMatch: { "Type": 1, "Value": "a" } } },
        { "Properties" : { $elemMatch: { "Type": 2, "Value": "b" } } }   
    ]
}

#

var query = 
Query.And(Query.WithinCircle("Location", centerX, centerY, radius),
Query.ElemMatch("Properties", Query.And(Query.EQ("Type", 1), Query.EQ("Value", "a"))),
Query.ElemMatch("Properties", Query.And(Query.EQ("Type", 2), Query.EQ("Value", "b"))));
+3

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