这是我检查文档是否存在的方式:varquery={};if(req.body.id){query._id={$ne:newrequire('mongodb').ObjectID.createFromHexString(req.body.id)};}Creditor.native(function(err,collection){collection.find({$or:[{name:req.body.name},{sapId:req.body.sapId},query]}).limit(-1).toArray(function(err,creditors){if(creditors.l