Use variables with regular expressions to find data in MongoDB (Meteor APP)

var variable = "car"; Items.find({"description": variable}).fetch();

Items.find({"description": /.*car.*/}).fetch();

Items.find({"description": /. *variable.*/}).fetch();
Items.find({"description": "/.*"+variable+".*/"}).fetch();

Items .find({"description": {$regex: ".*" + variable + ".*"}}).fetch();

I need to get data from Mongodb, depending on what I’m searching for. It works fine in the next two examples:
//Example 1;

var variable = "car"; Items.find({"description": variable} ).fetch();

//Example questions;

Items.find({"description": /.*car.*/}). fetch();

However, when I want to combine variables with regular expressions in MongoDB queries, it returns nothing, what am I doing wrong:

< /p>

Items.find({"description": /.*variable.*/}).fetch();
Items.find({"description": "/.*"+variable+" .*/"}).fetch();

Thanks in advance.

Indeed. You may not realize that the “/” and / Is different, and the latter does not have concatenation semantics (such as strings) as I know (but I may be wrong). The latter syntax is the inline/shorthand constructor of the RegExp class. This shows that it is easy to fix, Just use the new RegExp to explicitly create the regular expression.

However, in your case, I recommend using mongodb’s $regex construct:

Items.find({"description": {$regex: ".*" + variable + ".*"}}).fetch();

For more information, please refer to the documentation on $regex.