node.js - Retrieving value of count mongodb collection in a variable -

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i trying retrieve value of records collection in mongo db

here source.

exports.procc = function(req, res) {          db.collection('search', function(err, collection) {                     collection.count({'str':'car'},function(err, count) {                        console.log(count+' records');//prints 2 records                        c=count;                          });         });         console.log('records= '+c);//print 0 records  res.end(); };

the problem out of callback prints number of register, out of callback prints 0 , don't know how save value in variable.

because db.collection , collection.count asynchronous methods, c variable getting set after second console.log statement executed.

so want c has occur within collection.count callback.


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