How to use MongoRegex (MongoDB C# Driver)

Question

Has anyone have any idea how to use MongoRegex for the document search?

I attempted this, but returns nothing back:

var spec = new Document();
spec.Add("Name", new MongoRegex("/" + searchKey + "*/", "i"));
collection.Find(spec)

Wondering why it doesn't work, I tried to execute following command from the console:

db.things.find({"Name":/john*/i}) /* WORKS */
db.things.find({"Name":"/john*/i"}) /* DOESN'T WORK */

Is that possible that the driver applies double quotation to the regex?

Thanks..

Answer 1

I think you need to not include the "/"s in C#, i.e.,

spec.Add("Name", new MongoRegex(searchKey + "*", "i"));

Answer 2

After digging the source code, I finally found the answer :)

var spec = new Document();
spec.Add("Name", new MongoRegex(".*" + searchKey + ".*", "i"));
collection.Find(spec)

Answer 3

you just want a simple prefix query. Your regex is then ^ + searchKey. Also, this form will allow mongodb to use an index on Name.

var spec = new Document("Name", new MongoRegex(string.Format("^{0}",searchKey), "i"));

collection.Find(spec)