What does "./" (dot slash) refer to in terms of an HTML file path location?_问答_开发者

I know ../ means go up a path, but what does ./ mean exactly?

I was recently going through a tutorial and it seems to开发者_如何学JAVA be referring to just a file in the same location, so is it necessary at all? Can I just not use it if that's all it's doing?

/ means the root of the current drive;

./ means the current directory;

../ means the parent of the current directory.

You can use the following list as quick reference:

   /   = Root directory
   .   = This location
   ..  = Up a directory
   ./  = Current directory
   ../ = Parent of current directory
   ../../ = Two directories backwards

Useful article: https://css-tricks.com/quick-reminder-about-file-paths/

./ is the the folder that the working file is in:

So in /index.htm ./ is the root directory
but in /css/style.css ./ is the css folder.

This is important to remember because if you move CSS from /index.htm to /css/style.css the path will change.

.  = This location
.. = Up a directory

So, ./foo.html is just foo.html. And it is optional, but may have relevance if a script generated the path (relevance to the script that is, not how the reference works).

Yes, ./ means the current working directory. You can just reference the file directly by name, without it.

A fast and small recap about paths

Absolute paths

http://website.com/assets/image.jpg
IF the image is not on your domain - go look there for image

//website.com/assets/image.jpg
image loaded using http or https protocols

Relative paths

(For internal use if the image is on the same server)

image.jpg
image in the same place as the document calling the image!

./image.jpg
Same as above, image in the same place as the document calling the image!

/assets/image.jpg
Similar to Absolute Paths, just omitting the protocol and domain name
Go search my image starting from my root folder /, than into assets/

assets/image.jpg
this time assets is in the same place as the document, so go into assets for the image

../assets/image.jpg
From where the document is, go one folder back ../ and go into assets

../../image.jpg
go two folders back, there's my image!

../../assets/image.jpg
go two folders back ../../ and than go into assets

You are correct that you can omit it. It's useful only for clarity. There is no functional difference between it being there and not being there.

For example css files are in folder named CSS and html files are in folder HTML, and both these are in folder named XYZ means we refer css files in html as

<link rel="stylesheet" type="text/css" href="./../CSS/style.css" />

Here .. moves up to HTML
and . refers to the current directory XYZ

---by this logic you would just reference as:

<link rel="stylesheet" type="text/css" href="CSS/style.css" />

Yeah ./ means the directory you're currently in.

Do NOT use ./ as a web path when working directly with either CSS, HTML, or Web paths online! I explain why and what it is below...

TRUE WEB PATHS YOU SHOULD ALWAYS USE

../siblingfolder/file.html is a web path that starts from the folder you are in, goes up one parent folder (../), goes down into a new folder called "siblingfolder" and to "file.html" inside it. This is a type of relative path in the web world.

childfolder/file.html is another kind of web path that starts from the folder you are in and goes down to "childfolder" and "file.html" inside it. This is also as a relative path.

/subrootfolder/file.html is a web path that starts from the web root of your website and goes down from the web root into "subrootfolder" as an absolute path. Note: This path has the added advantage in that it works from any file and folder location on the server.

http://somewebsite.com/subrootfolder/file.html is another web path which works exactly the same as the ones above, but requires your web domain in the path. It still works but is very limiting because the web domain is hard-coded into the path. Some call this a fully qualified web path, which has some uses. The web browser also resolves most file paths to this address or an IP version of it.

AWKWARD AND RARELY USED PATHS

. is a shorthand for the current location or file context and is used in Linux and Unix to execute a compiled program in the current directory. That is why you don't see this used in Web Development much except by open source, non-Windows frameworks like Google Angular which was written by people stuck on open source platforms.

./ also resolves to the current directory and is atypical in Web but supported as a path in some open source frameworks. Because it resolves the same as no path to the current file directory its not used. Example: ./image.jpg = image.jpg. Even though it is used by software to identify a current folder location, because it is identical to the current software path or file location, it is the same as no path so redundant. Again, this is a relic of Unix operating systems that need path resolutions like this to run executables and resolve paths for security reasons. Its not a typical web path. That is why this syntax is redundant in HTML and web technologies.

//somewebsite.com/folder/folder/file.html this is a form of a fully qualified web URL resolution format. "//" tells the web browser to determine the fully qualified web URL/URI at runtime and concatenate the right http protocol onto the front of your path as so: https://mywebsite.com/folder/folder/file.html. It allows the browser to query one of many web domains and determine the most secure location or protocol to use: Either "http" or "https" as the most favorable and secure prefix. This is rarely used in most internal web paths but likely found in link href attribute paths in newer HTML5 elements and used when adding links to resources that may resolve to unknown dynamic secure socket layer connections at runtime that change.

PATH EQUIVALENTS

folder = /folder a relative path is the same as an absolute path in this case if the file accessing this child "folder" is located under the web root directory. Both paths would work the same for them.

../folder = /folder a relative path going up to a parent folder then down to "folder" is the same as the absolute path if the file accessing this path again is in the web root directory.

./folder = folder both relative paths start with the files current folder and point to the child "folder" under them no matter where these folders are located, so are the same. "./" is therefore redundant.

./file.html = file.html both relative paths point to the current folder and then to a "file.html" inside that folder. This means use of "./" is redundant.

./ = {no path} an empty path is the same as ./ in the web world so redundant again.

./ = / only true again if the file is under the web root folder. Again this means "./" is redundant.

MY WEB PATH RECOMMENDATIONS

ALWAYS use Absolute Paths ("/myfolder/myfile") whenever possible as they will always work from any file location in the web project, add no confusion to developers, moving files with absolute paths will not change paths, and they are easy to maintain and manage. The only drawback to absolute paths is if you move the files or folders being pathed to new locations (example: You move an image or CSS folder of files to a new location later in the project). That is why I recommend you manage paths via server-side virtual paths, application paths, or server-generated variables so you can change absolute paths dynamically as you move things around.

ALWAYS use Relative Web Paths ("../myfile") as a secondary option. These are a must for CSS file paths, CSS imported files, or font paths within CSS files. They should only be used if your web application is designed with many parallel applications running side-by-side under one domain, and have nested and heavily dependent resource files running inside them that must be separated. In that one case, you will often move these applications as one module deeper into the application making relative pathing more valuable. You will determine paths relative to the source files in that case and not relative to the web domain via absolute paths. As above, I would still manage paths via server-side or virtual application generated paths. This makes paths extremely simple, robust, and easy to dynamically update on the fly via server variables rather than inside scripts and dependencies which constantly evolve.

Here is PROOF that these UNIX "dot" paths fail on the web and why you should avoid them...

// IMAGE PATH JAVASCRIPT ERRORS
// These paths return broken image icons in browsers when using
// these unconventional UNIX local dot path conventions on the Web:
<img id="image1" src="./images/image1.png" />
<img id="image2" src="/images/.image2.png" />

NEVER use the other paths listed unless forced to by atypical, 3rd party, proprietary software conventions that use substandard pathing solutions that add confusion and added maintenance. :(

./ = Current directory

This is correct but as i figured out from some templates that i worked on before, the purpose of this identification is to remind the developer that the file to be accessed is not actually in the same directory as the HTML file being worked. Yes, I know it sounds weird.

Developers who use such definitions usually put a <base href=""> tag at the beginning of the HEAD block of the HTML page. Double quotes also indicate the directory they want to reach, so they don't have to define phrases like "../images" to access all of the image files that are not in the same directory as the HTML.

For example,

/main

/ /assets

/ / /css
/ / /images

/ / / /logo.png

/ /html

/ / /demo

/ / / /index.html

/ /plugins

every time you want to access the files in the images folder from the index.html file on a website with a directory structure like above, you need to use the src="../../assets/images" path. If you specify <base href="../../assets"> instead, you can now just use "images/" or "./images". Of course, remember, in this case, you will need to specify the file locations accordingly, as other page links will also be based on that <base> tag. So it's up to you whether you need to use it or not.

I did not wrote this to find the correct answer. This is my experience about the "./" usage so i wanted to share it. I hope it could help anybody.

In reference to the quick reference list, specifically you can use the following :

\.\ Root Directory + Current directory (Drive Letter)