The. Net project configuration file causes invalid runat = "server" and the Declaration Code cannot be automatically generated.

Recently, during project development, the. aspx. CS file ide prompts that codebehind referred to in the page declaration of all. aspx files cannot be found, and thus the objects cannot be automatically generated in the. Designer. CS file.CodeThis will make the project unable to reference the control variables of runat = "server" in the. CS file. After a day of troubleshooting and comparison, we found that in the. csproj project file I will

<Developmentserverport> 1560 </developmentserverport>

Changed

<Developmentserverport> 80 </developmentserverport>

It was originally intended to use port 80 for testing convenience. I did not expect this will cause the project codebehind to automatically generate the problem. It would be nice to change it to 1560.