Question

帮忙写个批处理

In this section, you will interface with the operating system using DOS commands.For each of the following tasks, list the correct DOS command. Note: While it is not necessary to perform these tasks on a computer, the assignment is structured for each task to be completed in sequence; that is to say, a task may depend on the state created by previous tasks. Name the batch file EXDIR.BAT. Include your name as a remark in EXDIR.BAT. Include the creation date as a remark in EXDIR.BAT. Include the function of EXDIR.BAT as a remark in EXDIR.BAT- redirects the output of dir C:\ to a file named by the user. The filename provided by the user is the first argument. A valid switch for the command dir is the optional second argument. If the file named by the user already exists, EXDIR.BAT immediately generates an error message and then exits without executing dir. The error message generated by EXDIR.BAT must display, "filename already exists, aborting EXDIR."

Answer 1

大概翻译了一下，根据这些英文我先写下要求。

创建一个批处理文件EXDIR.BAT，要求如下：
1.将你的姓名作为注释。
2.将文件的创建日期写入注释。
3.将文件的功能写入注释：将命令dir C:\ 的输出重定向到一个文件，该文件由用户指定。
4.将要输出到的文件名作为批处理文件的第一个参数。
5.批处理文件的第二个参数为可选项，如果存在，则应该是dir命令的开关（switch，如 / p）。
6.如果文件名已经存在，则批处理文件产生一个错误信息，并立即退出。
7.错误信息应该是："filename already exists, aborting EXDIR."

答案：
@echo off
(
echo @echo off
echo REM 姓名：%username%
echo REM 创建日期：%date%
echo REM 功能：将命令dir C:\ 的输出重定向到一个文件，该文件由用户指定。
echo if exist %%1 echo filename.already.exists.abortingEXDIR^&goto :eof
echo dir C:\ %%~2^>%%1
)>EXDIR.BAT
goto :eof

Answer 2

@echo off
echo @echo off
echo REM 姓名：%username%
echo REM 创建日期：%date%
echo REM 功能：将命令dir C:\ 的输出重定向到一个文件，该文件由用户指定。
echo if exist %%1 echo filename.already.exists.abortingEXDIR^&goto :eof
echo dir C:\ %%~2^>%%1