如何通过CMD从文本文件插入密码及自动解锁加密RAR文件？

Alright, let's tackle your two questions step by step—no manual typing required once we set this up!

First up, how to read a password stored in a text file and feed it into a CMD command. There are two common ways to do this, depending on the tool you're using:

• Method 1: Store the password in a variable
  This works great for tools that accept password parameters directly. First, read the password into a CMD variable, then pass that variable to your command:

  :: Read the first line of password.txt into the "pass" variable
  set /p pass=<password.txt
  :: Use the variable in your command (example with a hypothetical tool)
  some-tool.exe -u myusername -p %pass%
  

  Important: Make sure your password.txt only contains the password (no extra spaces or newlines at the end)—otherwise the variable will include those extra characters and your password will fail.

• Method 2: Pipe the password directly to the tool
  For tools that prompt for a password interactively, you can pipe the content of the text file straight into the tool's input:

  type password.txt | some-interactive-tool.exe
  

  This sends the password as if you typed it manually when the tool asks.

To do this, you'll need a command-line archive tool like WinRAR or 7-Zip (CMD can't natively handle RAR files). Here's how to set it up for both options:

Using WinRAR #

First, ensure WinRAR's rar.exe is in your system's PATH (or use the full path, like C:\Program Files\WinRAR\rar.exe).

• Option 1: Use a variable (clean and reliable)

  :: Read password from file
  set /p pass=<password.txt
  :: Extract the RAR file ("x" keeps folder structure; use "e" to extract all files to current directory)
  rar x -p"%pass%" your-protected-file.rar
  

  The -p"%pass%" flag tells WinRAR to use the password stored in the variable. Quoting %pass% ensures special characters (like !@#$) don't break the command.

• Option 2: Pipe the password directly
  WinRAR supports reading the password from standard input with the -p- flag:

  type password.txt | rar x -p- your-protected-file.rar
  

  This works just like the interactive pipe method—WinRAR grabs the password from the text file instead of asking you to type it.

Using 7-Zip (Alternative) #

If you prefer 7-Zip, the syntax is similar:

set /p pass=<password.txt
7z x your-protected-file.rar -p"%pass%"

Or with piping:

type password.txt | 7z x your-protected-file.rar -p-

Quick Safety & Usage Notes #

• Always double-check your password.txt—even a single extra newline or space will make the password invalid.
• Storing passwords in plain text is a security risk. Only use these methods for personal use or in a fully secure environment.

内容的提问来源于stack exchange，提问作者Mans1