Website address in robots file

How can i disallow a website address by robots file.

i need to disallow a site as [noparse]

if i use this code what will be

User-agent: *
Disallow: /[/noparse]

The robots.txt file needs to be placed in the top level directory for your site. So to disallow, you place the robots.txt file in its TLD and use

User-agent: *
Disallow: /

to disallow the entire site.

You can find more information at