ErrorDocument 404 /404.html
保存成.htaccess文件上传到网站的根目录。

/404.html是目录名和文件名，可以改成自己的名字。
QUOTE:

.htaccess文件是非常有用的

• Part 1 – Introduction介绍
• Part 2 - .htaccess Commande命令
• Part 3 - Password protection密码保护

Part 1 – Introduction介绍

Introduction 介绍

In this tutorial you will find out about the .htaccess file and thepower it has to improve your website. Although .htaccess is only afile, it can change settings on the servers and allow you to domany different things, the most popular being able to have your owncustom 404 error pages. .htaccess isn't difficult to use and isreally just made up of a few simple instructions in a textfile.
从本指南中，您可以学习到有关.htaccess文档及其功能，用以优化您的网站。尽管.htaccess只是一个文档，但它可以更改服务器的设置，允许您做许多不同的事情，最流行的功能是您可以创建自定义的“404error”页面。.htaccess 并不难于应用，只是在一个text文档中添加几条简单的指令而已。

Will My Host Support It? 我的主机支持它吗？

This is probably the hardest question to give a simple answer to.Many hosts support .htaccess but don't actually publicise it andmany other hosts have the capability but do not allow their usersto have a .htaccess file. As a general rule, if your server runsUnix or Linux, or any version of the Apache web server it will support.htaccess, although your host may not allow you to use it.
这可能很难用简单的答案来回答。许多主机支持.htaccess但实际上并不会明确声明，许多其他类型的主机有能力但并不允许他们的用户使用.htaccess文档。作为一般性的规则，如果你的主机使用Unix或Linux系统，或任何版本的Apache网络服务器，它一般来说是支持.htaccess的，尽管你的主机服务器可能不允许你使用它。

A good sign of whether your host allows .htaccess files is if theysupport password protection of folders. Todo this they will need to offer .htaccess (although in a few casesthey will offer password protection but not let you use .htaccess).The best thing to do if you are unsure is to either upload your own.htaccess file and see if it works or e-mail your web host and askthem.
你的主机是否允许.htaccess，很好的一个标志是它是否支持文件夹的密码保护。为此，他们将提供.htaccess支持（尽管少数情况下他们提供密码保护功能但不允许你使用.htaccess）。如果你不确定，最好的办法一是上传你自己的.htaccess文档看看是否有用，二是e-mail给你的主机服务商询问。

What Can I Do? 我该怎么做？

You may be wondering what .htaccess can do, or you may have readabout some of its uses but don't realise how many things you canactually do with it.
你可能疑惑.htaccess到底能做些什么，或者你可能曾知道它的一些功能但并不真正了解你实际到底可以用它来做多少事情。

There is a huge range of things .htaccess can do including:password protecting folders, redirecting users automatically,custom error pages, changing your file extensions, banning userswith certian IP addresses, only allowing users with certain IPaddresses, stopping directory listings and using a different fileas the index file.
.htaccess可以做大量范围的事情，包括：文件夹密码保护、用户自动重新指向、自定义错误页面、变更你的文件扩展名、屏蔽特定的用户IP地址、只允许特定的IP地址、停止目录表以及使用其他文件作为index文件。

Creating A .htaccess File 创建一个.htaccess文档

Creating a .htaccess file may cause you a few problems. Writing thefile is easy, you just need enter the appropriate code into a texteditor (like notepad). You may run into problems with saving thefile. Because .htaccess is a strange file name (the file actuallyhas no name but a 8 letter file extension) it may not be acceptedon certain systems (e.g. Windows 3.1). With most operatingsystems, though, all you need to do is to save the file by enteringthe name as:
创建.htaccess文档也许会给你带来几个问题。写文档很容易，你只需要在文字编缉器（例如：写字板）里写下适当的代码。然后，你可能会遇到保存文档的困难，因为.htaccess是一个古怪的文件名（文档事实上没有文件名，只有一个由8个字母组成的扩展名），一些系统（例如windows3.1）无法接受这样的文件名。在大多数的操作系统中，你需要做的是将文档保存成名为：

".htaccess"
(including the quotes). If this doesn't work, you will need to nameit something else (e.g. htaccess.txt) and then upload it to theserver. Once you have uploaded the file you can then rename itusing an FTP program.
（包括引号）。如果这也不行，你需要将其命名为其他的名字（例如htaccess.txt），再将其上传到服务器上，此后你就可以利用FTP软件来重命名它了。

Warning 警告

Before beginning using .htaccess, I should give you one warning.Although using .htaccess on your server is extremely unlikely tocause you any problems (if something is wrong it simply won'twork), you should be wary if you are using the Microsoft FrontPageExtensions. The FrontPage extensions use the .htaccess file so youshould not really edit it to add your own information. If you dowant to (this is not recommended, but possible) you should downloadthe .htaccess file from your server first (if it exists) and thenadd your code to the beginning.
在使用.htaccess之前，我必须给你一些警告。尽管在服务器上使用.htaccess绝对不太可能给你带来任何麻烦（如果有些东西错了，它只是没效用罢了），但如果你使用MicrosoftFrontPage Extensions你就需要小心些。FrontPageExtensions使用了.htaccess，因此你不能编辑它，加入你自己的信息。如果你需要（并不推荐，但是可能）你应该先从服务器上下载.htaccess文档（如果存在），之后在前面加上你的代码。

Custom Error Pages 自定义错误页

The first use of the .htaccess file which I will cover is customerror pages. These will allow you to have your own, personal errorpages (for example when a file is not found) instead of using yourhost's error pages or having no page. This will make your site seemmuch more professional in the unlikely event of an error. It willalso allow you to create scripts to notify you if there is an error(for example I use a PHP script on Free Webmaster Help toautomatically e-mail me when a page is not found).
我想介绍的.htaccess第一个应用是自定义错误页面，这使得你可以拥有自己的、个性化的错误页面（例如找不到文件时），而不是你的服务商提供的错误页或没有任何页面。这会让你的网站在出错的时候看上去更加专业。你还可以利用脚本程序在发生错误的时候通知你（例如我使用FreeWebmaster Help的PHP脚本程序，当找不到页面的时候自动e-mail给我）。

You can use custom error pages for any error as long as you knowits number (like 404 for page not found) by adding the following toyour .htaccess file:
任何你知道代码的错误（像404找不到页面），你都可以将其变成自定义页面，要做的只是在.htaccess文件里加入以下一段：

ErrorDocument errornumber /file.html
For example if I had the file notfound.html in the rootdirect
ory of my site and I wanted to use it for a 404 error I woulduse:
例如，如果我的根目录下有一个nofound.html文档，我想使用它作为404error的页面：

ErrorDocument 404 /notfound.html
If the file is not in the root directory of your site, you justneed to put the path to it:
如果文件不在网站的根目录下，你只需要把路径设置为：

ErrorDocument 500 /errorpages/500.html
These are some of the most common errors:
以下是一些最常用的错误：

401 - Authorization Required
400 - Bad request
403 - Forbidden
500 - Internal Server Error
404 - Wrong page
Then, all you need to do is to create a file to display when theerror happens and upload it and the .htaccess file.
这样，你要做的只是生成一个错误显示文档，然后把它们上传。

Part 2 - .htaccess 命令

Introduction 介绍

In the last part I introduced you to .htaccess and some of itsuseful features. In this part I will show you how to use the.htaccess file to implement some of these.
上一部分中我已经将你引入了.htaccess以及它的一些有用的功能，在这一部分里，我将向您演示如何应用.htaccess文档去实现这些功能。

Stop A Directory Index From Being Shown 停示显示目录索引

Sometimes, for one reason or another, you will have no index filein your directory. This will, of course, mean that if someone typesthe directory name into their browser, a full listing of all thefiles in that directory will be shown. This could be a securityrisk for your site.
有些时候，由于某种原因，你的目录里没有index文件，当然这样意味着如果有人在浏览器地址栏键入了该目录的路径，该目录下所有的文件都会显示出来，这造成了网站的安全威胁。

To prevent against this (without creating lots of new 'index'files, you can enter a command into your .htaccess file to stop thedirectory list from being shown:
为了避免这种情况（而不必创建一堆的新index文档），你可以在你的.htaccess文档中键入以下命令，用以阻止目录索引的显示：

Options -Indexes
Deny/Allow Certian IP Addresses 阻止/允许特定的IP地址

In some situations, you may want to only allow people with specificIP addresses to access your site (for example, only allowing peopleusing a particular ISP to get into a certian directory) or you maywant to ban certian IP addresses (for example, keeping disruptivememembers out of your message boards). Of course, this will onlywork if you know the IP addresses you want to ban and, as mostpeople on the internet now have a dynamic IP address, so this isnot always the best way to limit usage.
有些情况下，你可能只想允许某些特定IP的用户可以访问你的网站（例如：只允许使用特定ISP的用户进入某个目录），或者你想拦截某些特定的IP地址（例如：将低级用户隔离于你的信息面版外）。当然，这只在你知道你想拦截的IP地址时才有用，然而现在网上的大多数用户都使用动态IP地址，所以这并不是限制使用的常用方法。

You can block an IP address by using:
你可以使用以下命令拦截一个IP地址：

deny from 000.000.000.000
where 000.000.000.000 is the IP address. If you only specify 1 or 2of the groups of numbers, you will block a whole range.
被拦截的IP地址则为000.000.000.000，如果你只指定其中1或2个代码组，你可以拦截整个区域的地址。

You can allow an IP address by using:
你可以使用以下命令允许一个IP地址的访问：

allow from 000.000.000.000
where 000.000.000.000 is the IP address. If you only specify 1 or 2of the groups of numbers, you will allow a whole range.
被允许的IP地址则为000.000.000.000，如果你只指定其中1或2个代码组，你可以允许整个区域的地址。

If you want to deny everyone from accessing a directory, you canuse:
如果你想阻止所有人访问该文件目录，你可以使用：

deny from all
but this will still allow scripts to use the files in thedirectory.
但这将仍然允许脚本程序使用这个目录下的文档。

Alternative Index Files 替代的index文档

You may not always want to use index.htm or index.html as yourindex file for a directory, for example if you are using PHP filesin your site, you may want index.php to be the index file for adirectory. You are not limited to 'index' files though. Using.htaccess you can set foofoo.blah to be your index file if you wantto!
也许你不想一直使用index.htm或index.html来作为目录的索引文档，例如你的站点使用PHP文档，你会想使用index.php来作为该目录的索引文档。当然也不必局限于“index”文档，如果你愿意，你尽管使用foofoo.balh来作为你的索引文档！

Alternate index files are entered in a list. The server will workfrom left to right, checking to see if each file exists, if none ofthem exisit it will display a directory listing (unless, of course,you have turned this off).
替代的索引文档可以排成一个列表，服务器会从左至右进行寻找，看看哪个文档在真实的目录中存在。如果一个也找不到，它将会把目录清单显示出来（当然除非你关闭了显示目录文件清单）。

DirectoryIndex index.php index.php3 messagebrd.pl index.htmlindex.htm
Redirection 重新指向

One of the most useful functions of the .htaccess file is toredirect requests to different files, either on the same server, oron a completely different web site. It can be extremely useful ifyou change the name of one of your files but allow users to stillfind it. Another use (which I find very useful) is to redirect to alonger URL, for example in my newsletters I can use a very shortURL for my affiliate links. The following can be done to redirect aspecific file:
.htaccess其中一个极其有用的功能，就是将请求重新指向站内或站外的不同文档。当你改变了一个文档名称时但仍然想让用户仍然可以用旧链接找到它，这个时候此功能将变得极其有用。另一个应用（我发现的很有用的）是重新指向一个长URL，例如在我的时事信息中，我可以使用一个很简短的URL来指向我的联合链接。以下是一个重新指向特定文档的例子：

Redirect /location/from/root/file.ext http://www.othersite.com/new/file/location.xyz
In this above example, a file in the root directory calledoldfile.html would be entered as:
上述的例子中，访问在root目录下的名为oldfile.html可以键入：

/oldfile.html
and a file in the old subdirectory would be entered as:
访问一个旧次级目录中的文件可以键入：

/old/oldfile.html
You can also redirect whole directoires of your site using the.htaccess file, for example if you had a directory calledolddirectory on your site and you had set up the same files on anew site at: http://www.newsite.com/newdirectory/ you couldredirect all the files in that directory without having to specifyeach one:
你也可以使用.htaccess将整个网站的目录都做重新指向，假如你的网站上有一个名为olddirectory的目录，并且你已经在一个新网站http://www.newsite.com/newdirectory/上建立了与上相同的文档，你可以将旧目录下所有的文件做一次重新指向而不必一一声明：

Redirect /olddirectory http://www.newsite.com/newdirectory
Then, any request to your site below /olddirectory will beeredirected to the new site, with the
extra information in the URL added on, for example if someone typedin:
这样，任何指向到站点中/olddirectory的请求都将被重新指向新的站点，包括附加的额外URL信息。例如有人键入：

They would be redirected to:
请求将被重新指向到：

This can prove to be extremely powerful if used correctly.
如果正确使用，本功能将极其强大。

Part 3 – 密码保护

Introduction 介绍

Although there are many uses of the .htaccess file, by far the mostpopular, and probably most useful, is being able to relaiblypassword protect directories on websites. Although JavaScript etc.can also be used to do this, only .htaccess has total security (assomeone must know the password to get into the directory, there areno 'back doors')
尽管有各种各样的.htaccess用法，但至今最流行的也可能是最有用的做法是将其用于网站目录的可靠的密码保护。尽管JavaScrip等也能做到，但只有.htaccess具有完美的安全（即访问者必须知晓密码才可以访问目录，并且绝无“后门”可走）。

The .htaccess File

Adding password protection to a directory using .htaccess takes twostages. The first part is to add the appropriate lines to your.htaccess file in the directory you would like to protect.Everything below this directory will be password protected:
利用.htaccess将一个目录加上密码保护分两个步骤。第一步是在你的.htaccess文档里加上适当的几行代码，再将.htaccess文档放进你要保护的目录下：

AuthName "Section Name"
AuthType Basic
AuthUserFile /full/path/to/.htpasswd
Require valid-user
There are a few parts of this which you will need to change foryour site. You should replace "Section Name" with the name of thepart of the site you are protecting e.g. "Members Area".
有几个小部分你可能需要根据你的网站情况而修改一下。用被保护部分的名字替换掉”Section Name”，例如"MembersArea"。

The /full/parth/to/.htpasswd should be changed to reflect the fullserver path to the .htpasswd file (more on this later). If you donot know what the full path to your webspace is, contact yoursystem administrator for details.
另外/full/parth/to/.htpasswd应该替换为指向.htpasswd文档（后面详述该文档）的完整服务器路径。如果你不知道你网站空间的完整路径，询问一下你的系统管理员。

The .htpasswd File

Password protecting a directory takes a little more work than anyof the other .htaccess functions because you must also create afile to contain the usernames and passwords which are allowed toaccess the site. These should be placed in a file which (bydefault)should be called .htpasswd. Like the .htaccess file, this is a filewith no name and an 8 letter extension. This can be placed anywherewithin you website (as the passwords are encrypted) but it isadvisable to store it outside the web root so that it is impossibleto access it from the web.
目录的密码保护比.htaccess的其他功能要麻烦些，因为你必须同时创建一个包含用户名和密码的文档，用于访问你的网站，相关信息（默认）应位于一个名为.htpasswd的文档里，像.htaccess一样，.htpasswd也是一个没有文件名且具有8位扩展名的文档，可以放置在你网站里的任何地方（此时密码应加密），但建议你将其保存在网站根目录外，这样通过网络就无法访问到它了。

Entering Usernames And Passwords 输入用户名和密码

Once you have created your .htpasswd file (you can do this in astandard text editor) you must enter the usernames and passwords toaccess the site. They should be entered as follows:
创建好.htpasswd文档后（可以通过文字编辑器创建），下一步是输入用于访问网站的用户名和密码，应为：

username:password
where the password is the encrypted format of the password. Toencrypt the password you will either need to use one of the premadescripts available on the web or write your own. There is a goodusername/password service at the KxS site which will allow you toenter the user name and password and will output it in the correctformat.
“password”的位置应该是加密过的密码。你可以通过几种方法来得到加密过的密码：一是使用一个网上提供的permade脚本或自己写一个；另一个很不错的username/password加密服务是通过KxS网站，这里允许你输入用户名及密码，然后生成正确格式的密码。

For multiple users, just add extra lines to your .htpasswd file inthe same format as the first. There are even scripts available forfree which will manage the .htpasswd file and will allow automaticadding/removing of users etc.
对于多用户，你只需要在.htpasswd文档中新增同样格式的一行即可。另外还有一些免费的脚本程序可以方便地管理.htpasswd文档，可以自动新增/移除用户等。

Accessing The Site 访问网站

When you try to access a site which has been protected by .htaccessyour browser will pop up a standard username/password dialog box.If you don't like this, there are certain scripts available whichallow you to embed a username/password box in a website to do theauthentication. You can also send the username and password(unencrypted) in the URL as follows:
当你试图访问被.htaccess密码保护的目录时，你的浏览器会弹出标准的username/password对话窗口。如果你不喜欢这种方式，有些脚本程序可以允许你在页面内嵌入username/password输入框来进行认证，你也可以在浏览器的URL框内以以下方式输入用户名和密码（未加密的）：

http://username:password@www.website.com/directory/
Summary 小结

.htaccess is one of the most useful files a webmaster can use.There are a wide variety of different uses for it which can savetime and increase security on your website.
.htaccess是一个站点管理员可以应用的一个强大的工具，有更多的变化以适应不同的用途，可以节约时间及提高网站的安全性。

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