Cannot read property 'desphoto' of undefined;at pages/details/details page topic_preview function

TypeError: Cannot read property 'desphoto' of undefined

at l.topic_preview (weapp:///pages/details/details.js:106:46)

at l.<anonymous> ([publib]:2:1571255)

at Object.r.safeCallback ([publib]:2:1307179)

at [publib]:2:1484778

at r ([publib]:2:1434475)

at [publib]:2:1434597

at [publib]:2:665032

at Object.y ([publib]:2:74458)

at Object.value [as subscribeHandler] (C:\Users\Administrator\AppData\Roaming\Tencent\微信开发者工具\package.nw\js\unpack\remote-helper.js:55:2176)

at [VM 37]:1:58