Click the child nodes of the tree control, when there is no data, I want it to bring up a prompt box,

But when the returned json data is empty, my alert () how do not tip, feel alert didn't work

CodePudding user response:

if (! Response. The data) is equal to the if (response.data=https://bbs.csdn.net/topics/=null) clearly response. The data is not null, you should add a length judgment
if (! The response. The data & amp; & The response. The data. The length & lt;=0)

CodePudding user response:

Thanks, solved