问题
I noticed Joomla, Wordpress and other CMSs have blank index.html files in ALL their sub folders to prevent people from peeking into the folder structure. My question is why can't they forbid folder viewing using the .htaccess file instead of putting a blank index.html file into all the folders. What's the difference and why have they chosen index.html?
回答1:
Turning off folder 'Indexes' is best done in the master httpd.conf or vhosts.conf file rather than local .htaccess files.
Joomla (and Mambo before it) have been around quite a while and are used widely on shared hosting servers. The decision was taken to use index.html files as a safe fallback given the 'mixed' nature of shared hosting. Obviously .htaccess files are apache only, can cause server 500 errors if present on servers not expecting them or if they contain directives not supported by certain server setups. Consequently by default Joomla doesn't ship with a .htaccess file as such. There is a htaccess.txt file which the user needs to put in place manually if they activate certain features. It is assumed that a user knowledgeable enough to put the file in place will understand the consequences and if it does kill their site they will immediately understand the cause - due to the error immediately following their actions.
As server setups have advanced there is (sometimes heated) discussion about the current validity of the use of index.html files - but for now the policy is that all add-ons should ship with 'blank' index.html files in all folders.
来源：https://stackoverflow.com/questions/8337060/blank-index-html-in-cms-softwares-instead-of-htaccess