CountDocuments equivalent before mongodb 4.0

[Zhihong GUO]

Hello, 

I am developing a feature based on Collection.CountDocuments, but I just notice that this API available after v4.0. Is there any equivalent function able to be used on v3.6?

Thanks,

James

[Isabella Siu]

Answered in https://community.mongodb.com/t/managing-schema-changes-with-mongodb/1137. For future reference, we are hoping to move all Google Group communication to the community forums, so it's sufficient to just ask the question there rather than both places. 

[Divjot Arora]

Small edit to the answer above: the correct link for the community forums answer is https://community.mongodb.com/t/whats-the-equivalent-function-of-countdocuments-before-4-0/1259/4.