javascript - in nodejs access variable outside callback like gloabal varaible -


this question has answer here:

    var coll= '';     function test(callback){         mongoclient.connect(url, function(err, db) {           if(err) throw err;           coll=db           callback(coll);         });     }      test();     console.log(coll)

this code. when print 'coll' variable says undefined. how access variable outside of callback. getting error callback not function

you not passing callback function argument test() function, therefore statement in test() function: callback(coll), throw error ending script prior calling console.log(coll).


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