问题
I'm having an issue where, periodically, I am unable to type into any input/textareas on Internet Explorer. I'm working primarily with IE9 at the moment.
When I click on an input, the JS click handler (which empties placeholder text) runs, and the active css is applied. However, the cursor does not appear and I can't type. If I tab to an input field, and start typing, everything starts working again.
I have a fair bit of JS running, but no errors running. I suspected TinyMCE had something to do with it, but it also happens when there are no editors on the page, so that doesn't seem to be it either. If you don't have an answer, I'd love an idea of what could be happening here that I could look into more, since I'm a bit stumped.
回答1:
I eventually solved this. It was a strange and nasty issue with TinyMCE, where TinyMCE was being destroyed while the cursor was inside the main window. Fix was to explicitly focus out before it gets destroyed.
回答2:
I had a similar issue once with I.E. where I was using .split to make sure the input box was not empty when gaining focus. However, I.E. did not support .split and would crash my js. I had to write my own and it ended up working out. Not sure if this in any way applies to what you are doing, but I thought I would just throw it out there.
回答3:
Since you have lots of javascript on the page, a likely reason would be either a naming conflict or even more likely a js crash. Traverse your code for the 200th time.
来源：https://stackoverflow.com/questions/8978235/why-can-i-sometimes-not-type-into-my-input-in-ie