Writing javascript code for IE _ javascript skills

Sometimes we need to write separate JS processing code for the compatibility of some IE files. This is just a simple one. For compatibility purposes, there are multiple methods to achieve it. I have compiled a little bit, if you are interested, you can understand that it may be helpful to you. Sometimes we need to write separate JS processing code for some IE compatibility. There are multiple approaches:

1. Check navigation. userAgent to determine whether it is IE, and then write the processing code of the IE Branch:
2. by declaring the @ cc_on statement, you can enable Conditional compilation in the comments of the script so that non-ie browsers will recognize it as comments and ignore it (measurement, this method will apply to the IE6-9 !) :

The Code is as follows:

/* @ Cc_on @ if (@ _ jscript)
Alert ("hello world ");
@ End @*/