I have written a small project and everything works well in Chrome and FF, but when I test it in IE( IE 9 and 10 works well while IE8 not),I meet a lot problems.

1.In grid, when I click some cells ,it will lose focus after 1 or 2 minutes,but when i click it again ,it will not happen again.

2.When I insert an empty record into the grid and update it ,the store won't be updated.(I used console.log() to show the store.getAt(0).getData())

3.When I add DOCTYPE into the html document it throw a error in IE8(ext-debug.js 12270 style[hook.name] = value invalid argument),when I remove the DOCTYPE,the textfield and someother component don't show correctly.

Anyone has met these before or can tell me how to fix it ?

PS: I use ExtJs 4.1.1