如何在 Z2D50972FCECD70612895456 中使用 C# mongo Db 驱动程序将多个文档组合/合并到一个 c# object

Question

I have three document on the mongdo DB like in below example (grand parent, parent and child document). I wanted the object to include like in result using the C# mondoDB driver. Scenario is If grand child does not have property/value (eg. gprop2,fprop2 ) then it will get the property/value from the parent/gran parent but at the same time if all document have same property(eg. "cprop1"), then the grad child will override the value from both parent and grad parent. Also grad child can have its own property("sprop2") which should include on the final result. I have got the final result by manually checking/copying the property/value down to child but I am looking for the efficient solution. Is there way to achieve it using the C# mongoDb drive in .NET core?

Grand Parent Doc

  {
    "cprop1": "gval1",
    "gprop2": "gval2"
    "gppcrop2": "gpcval22",
    "assets" : [
        {
          "gasset1": "gassetVal1",
          "gcasset1": "gcassetVal1"
        },......
     ]
  }

Parent Doc

  {
    "cprop1": "fval1",
    "fprop2": "fval2",
    "gppcrop2": "gpcval33",
    "assets" : [
        {
          "passet1": "passetVal1",
          "gcasset1": "gcassetVal2"
        },.......
     ]
  }

Child Doc

  {
    "cprop1": "sval1",
    "sprop2": "sval2",
    "assets" : [
        {
          "sasset1": "sassetVal1",
          "gcasset1": "gcassetVal3"
        },..........
     ]
  }

Final Result

{

    "cprop1": "sval1",
    "gprop2": "gval2",
    "fprop2": "fval2",
    "gppcrop2": "gpcval33",
    "sprop2": "sval2",
    "assets": [
    {
     "gasset1": "gassetVal1",
     "passet1": "passetVal1"
     "sasset1": "sassetVal1",
     "gcasset1": "gcassetVal3"
    },....
  ]

  }

Answer 1

You can do this with Merge method.

static void Main(string[] args)
{
    BsonDocument gp = new BsonDocument("cprop1", "gval1").Add("gprop2", "gval2").Add("gppcrop2", "gpcval22");
    BsonDocument parent = new BsonDocument("cprop1", "fval1").Add("fprop2", "fval2").Add("gppcrop2", "gpcval33");
    BsonDocument child = new BsonDocument("cprop1", "sval1").Add("sprop2", "sval2");

    child.Merge(parent);
    child.Merge(gp);

    Console.WriteLine(child.ToJson(new MongoDB.Bson.IO.JsonWriterSettings() { Indent = true }));

}

You get

{
  "cprop1" : "sval1",
  "sprop2" : "sval2",
  "fprop2" : "fval2",
  "gppcrop2" : "gpcval33",
  "gprop2" : "gval2"
}