将我的头撞在桌子上很多小时后，我找到了解决这个奇怪问题的答案.原来bootstrap.min.js脚本正在干扰JavaScript intellisense.因此，我只是在_references.js文件中注释了该脚本.另外，我将自动同步更改为false，然后智能感知又回来了.

After many hours of banging my head against my desk, I found the answer to this weird issue. Turns out that the bootstrap.min.js script was interfering with the JavaScript intellisense. So I just commented out the script in my _references.js file. Also, I changed the autosync to false and instantly the intellisense came back.