Why is JavaScript runtime error when running in design mode?

Dong Lam Trien

6y897.NET

In VS2010 design mode when I press F5 to run the program, I get the following error:

1. JavaScrip runtime error: Unable to set property 'showmessagebox' of undefined or null reference.

2. JavaScrip runtime error: Unable to set property 'evaluationfunction' of undefined or null reference.

When this error I have to press Continue will continue to run, how to fix it ? You see my attached photo file.

https://imgur.com/50sExkp

https://imgur.com/11T0RiN

4 Replies

Know the answer? Post it — somebody with the same question will find it here.

The error occurred when I use IE, other browsers do not have this error

can you share ur code, it is diffcul to say why this error occured..

you can find few knowl issue solution here

https://stackoverflow.com/questions/27038560/javascript-runtime-error-unable-to-set-property