读取客户端和服务器端的文件之间的区别

Question

What exactly is the difference between accessing a file through HTML (e.g. <img src="xxx.jpg">) or JavaScript, and using PHP to read a file. The file is still just on the server in both cases, isn't it?

What makes using PHP to access the server's file system different to someone just typing in the URL of the file (provided they know what it is)?

Answer 1

For static files like (images, HTML, etc) there is no difference, if you directly enter the file URI or read it internally and print the buffer through PHP (at this case the file URI will change for sure).

For dynamic files (PHP files), the same concept is true, if you enter the file URI directly you will get the output of that file, and if you read it internally (There are two types: include and read its source). but in most cases, PHP files are designed for execution not for printing the source, therefore, in both cases:

• When you try to read static files by PHP its just resource wasting if there is no need to use PHP.