                        課程
                    
                        /前端開發
                        
                            /Node.js
                        
                        /node+mongodb 建站攻略（一期）

_id是什么，控制臺輸出未定義？

TypeError:?Cannot?read?property?'_id'?of?undefined
????at?E:\node\node\server.js:134:25
????at?Layer.handle?[as?handle_request]?(E:\node\node\node_modules\express\lib\router\layer.js:95:5)
????at?next?(E:\node\node\node_modules\express\lib\router\route.js:137:13)
????at?Route.dispatch?(E:\node\node\node_modules\express\lib\router\route.js:112:3)
????at?Layer.handle?[as?handle_request]?(E:\node\node\node_modules\express\lib\router\layer.js:95:5)
????at?E:\node\node\node_modules\express\lib\router\index.js:281:22
????at?Function.process_params?(E:\node\node\node_modules\express\lib\router\index.js:335:12)
????at?next?(E:\node\node\node_modules\express\lib\router\index.js:275:10)
????at?E:\node\node\node_modules\body-parser\lib\read.js:130:5
????at?invokeCallback?(E:\node\node\node_modules\raw-body\index.js:224:16)
????at?done?(E:\node\node\node_modules\raw-body\index.js:213:7)
????at?IncomingMessage.onEnd?(E:\node\node\node_modules\raw-body\index.js:273:7)
????at?emitNone?(events.js:106:13)
????at?IncomingMessage.emit?(events.js:208:7)
????at?endReadableNT?(_stream_readable.js:1056:12)
????at?_combinedTickCallback?(internal/process/next_tick.js:138:11)

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