如何使用MongoDB和C＃驱动程序构建复杂查询？

Question

I have developed a simple API which allows you to build up an array of search criteria within a MongoDB Collection. I now need to be able to convert this array into an actual Mongo Query, and this part is where I am having extreme difficulty.

Ideally I am after some syntax that will allow me to do the following pseudo code:

var query = new QueryBuilder();
foreach (var group in groups)
{
    switch (group.Condition)
    {
        case GroupCondition.Or:
            query.Or(group.Queries);
        break;
        case GroupCondition.And:
            query.And(group.Queries);
        break;
    }
}
return myCollection.FindAs(type, query);

I actually want to build up slightly more complex queries, but ultimately I am after the functionality to dynamically build up my queries with objects as seen in my pseudo code above.

Feel free to ask me for additional details if I have not made myself clear enough about what I am trying to achieve.

Answer 1

Seems like you have the right idea... There is a class called Query that is essentially a query builder without the instantiation.

using MongoDB.Driver.Builders;

Query.And, Query.Or, etc... are all there. It is the same thing that is used underneath the linq provider to build up complex queries.