改变Visual Assist的Cache存放目录

在使用Visual Assist (VC助手)的时候，会在C盘(系统盘)留下很多cache文件，都是以前保存的项目中的解析索引文件，久而久之会越来越大，侵占C盘空间。查了下解决的办法如下： (根据tomato官方BBS的说法，实测有效)
By default Visual Assist X stores its symbol database in the following directory tree:

Under Windows 2000 and Windows XP:
C:/Documents and Settings/<USERNAME>/Local Settings/Application Data/VisualAssist/

Under Windows Vista:
C:/Users/<USERNAME>/AppData/Local/VisualAssist/

If you are using Visual Assist X 1614 and above then you can tell Visual Assist X to use a different directory by setting the registry key:

HKCU / Software / Whole Tomato / UserDataDir = "C:/new_path/"

You will need to create this String value since Visual Assist X does not create it by default.

VisualAssist X will store the symbol database, history, cache and temporaryfiles in this new directory tree. Simply delete the key to revert backto the default locations for the symbol database.

Note you need to close all instances of the IDE before setting this registry key.

也就是在注册表中自己加一个项，即可。