Concerning the ExtJS error "exceptions are thrown and not caught"

An error message was reported recently when ExtJS was used to build the webpage interface. The prompt in IE is as follows:

Exception thrown and not caught, row 19 ....

The Firefox prompt is as follows:

Uncaught exception: No center region defined in BorderLayout westpanel.

I haven't found any problems after debugging according to the error information of IE. I didn't know much about JS Code. After reading the prompts of Firefox, we can see that the center region is not defined in the westpanel with layout as border. To prevent such errors, you must delete layout as border or add center region. Obviously, if this panel does not have a sub-panel (items), you do not need to set it to border layout. Check the ExtJS3.1.1 API documentation. The border layout prompt is as follows:

1. any container using the BorderLayout must have a child item with region: 'center '. the child item in the center region will always be resized to fill the remaining space not used by the other regions in the layout.

2. Any child items with a region of west or east must have width defined (an integer representing the number of pixels that the region shocould take up ).

3. Any child items with a region of north or south must have height defined.

I already made it very clear, but I didn't pay attention to it when I used it.

In the future, you will need to use Firefox Firebug for debugging.