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Editor to share with you what are the necessary command parameters to write batch processing skills, I believe that most people do not know much, so share this article for your reference, I hope you will learn a lot after reading this article. Let's learn about it!

First of all, the batch file is a text file, each line of this file is a DOS command (most of the time we execute the command line at the DOS prompt), you can use Edit under DOS or Windows notepad (notepad) and any text file editing tools to create and modify batch files.

Secondly, a batch file is a simple program, which can control the flow of commands through conditional statements (if) and process control statements (goto), and loop statements (for) can also be used in batch processing to loop a command. Of course, the programming ability of batch files is very limited and irregular compared with C language and other programming statements. The program statements of batch processing are DOS commands (including internal and external commands), and the ability of batch processing mainly depends on the commands you use.

Third, each written batch file is equivalent to an external command of DOS, and you can put its directory in your DOS search path (path) so that it can run anywhere. A good practice is to create a bat or batch directory on your hard drive (for example, C:\ BATCH), and then put all the batch files you write into that directory, so that as long as c:\ batch is set in path, you can run all the batch programs you write anywhere.

Fourth, in DOS and Win9x/Me systems, C: disk root directory of the AUTOEXEC.BAT batch file is automatically run batch file, each system startup will automatically run the file, you can run the system every time you start the command to run into the file, such as setting the search path, call the mouse driver and disk cache, set system environment variables, and so on. The following is an example of autoexec.bat running under Windows 98:

@ ECHO OFF

PATH C:\ WINDOWS;C:\ WINDOWS\ COMMAND;C:\ UCDOS;C:\ DOSTools;C:\ SYSTOOLS;C:\ WINTOOLS;C:\ BATCH

LH SMARTDRV.EXE / X

LH DOSKEY.COM / INSERT

LH CTMOUSE.EXE

SET TEMP=D:\ TEMP

SET TMP=D:\ TEMP

The role of batch processing

To put it simply, the function of batch processing is to execute multiple commands automatically and sequentially.

Let's start with the simplest application: when you start the wps software, you must execute it every time (> the previous content represents the DOS prompt):

C:\ > cd wps

C:\ WPS > spdos

C:\ WPS > py

C:\ WPS > wbx

C:\ WPS > wps

Do you find it troublesome to do this every time before using WPS?

Well, with batch processing, you can simplify these troublesome operations. First, let's write a runwps.bat batch file with the following contents:

@ echo off

C:

Cd\ wps

Spdos

Py

Wbx

Wps

Cd\

In the future, every time we enter wps, we only need to run the batch file runwps.

Common command

Echo, @, call, pause, rem (tip: use:: instead of rem) are the most commonly used commands for batch files, so let's start with them.

Echo indicates the characters after this command is displayed

Echo off means that all commands that run after this statement do not display the command line itself

@ is similar to echo off, but it is added to the front of each command line, indicating that the command line is not displayed at run time (only the current line is affected).

Call calls another batch file (if you call another batch file directly without call, you will not be able to return the current file and execute subsequent commands for the current file after executing that batch file).

Pause running this sentence pauses the execution of the batch and displays Press any key to continue... on the screen Wait for the user to press any key before continuing

Rem indicates that the characters after this command are interpretation lines (comments), which are not executed, but are only for future reference (equivalent to comments in the program).

Example 1: edit the a.bat file with edit, enter the following contents and save it to c:\ a.bat. After executing the batch file, you can write all the files in the root directory to a.txt, start UCDOS, enter WPS and other functions.

The contents of the batch file are as follows: command comments:

@ echo off does not display subsequent command line and current command line

Dir c:\ *. * > a.txt writes the list of files on disk c to a.txt

Call c:\ ucdos\ ucdos.bat calls ucdos

Hello, echo. Display "Hello".

Pause pauses and waits for the button to continue

Rem ready to run wps Note: prepare to run wps

Cd ucdos enters the ucdos directory

Wps runs wps

Parameters for batch files

Batch files can also use parameters like C language functions (equivalent to command-line arguments for DOS commands), which requires a parameter representation of "%".

% [1-9] represents a parameter, which is a string separated by a space (or Tab) after the file name when running a batch file. Variables can range from% 0 to% 9jue% 0 to represent the batch command itself, and other parameter strings are represented in the order of% 1 to% 9.

Example 2 C: there is a batch processing file named f.bat in the root directory, which contains:

@ echo off

Format 1

If you execute C:\ > f a:

Then when executing f.bat,% 1 represents a format, so format% 1 is equivalent to format a, so the above command is actually executed at run time:

Example 3 C: the batch processing file under the root directory is named t.bat, which contains:

@ echo off

Type 1

Type 2

Then run C:\ > t a.txt b.txt

% 1: indicates a.txt

% 2: indicates b.txt

So the above command will display the contents of the a.txt and b.txt files sequentially.

Special command

If goto choice for is a more advanced command in batch files, and if you are adept at using these commands, you are an expert in batch files.

First, if is a conditional statement, which is used to determine whether the specified conditions are met, thus deciding to execute different commands. There are three formats:

1. If [not] "Parameter" = = "string" Command to be executed

If the parameter is equal to the specified string (not for inequality, the same below), the condition holds, run the command, otherwise run the next sentence.

Example: if "% 1" = "a" format a:

2. If [not] exist [path\] File name commands to be executed

If there is a specified file, the condition is established, run the command, otherwise run the next sentence.

Such as: if exist c:\ config.sys type c:\ config.sys

Indicates that if a c:\ config.sys file exists, its contents are displayed.

3. Commands to be executed by if errorlevel

Many DOS programs will return a numeric value to represent the result (or status) of the program after running. The return value of the program can be judged by the if errorlevel command, and different commands must be executed according to different return values (the return values must be arranged in the order from largest to smallest). If the return value is equal to the specified number, the condition holds, run the command, otherwise run the next sentence.

Such as if errorlevel 2 goto x2

Second, when the goto batch file runs here, it will jump to the label specified by goto (the label is label, followed by a standard string to define). Goto statements are generally used in conjunction with if to execute different command groups according to different conditions.

Such as:

Goto end

: end

Echo this is the end

The label is defined by ": string", and the line of the label is not executed.

Third, choice uses this command to allow the user to enter a character (for selection), so as to return different errorlevel according to the user's choice, and then cooperate with if errorlevel to run different commands according to the user's choice.

Note: choice commands provide external commands for DOS or Windows systems, different versions of choice command syntax will be slightly different, please use choice /? Check the usage.

Command syntax for choice (this syntax is the syntax for the choice command in Windows 2003, and the command syntax for other versions of choice is more or less the same):

CHOICE [/ C choices] [/ N] [/ CS] [/ T timeout / D choice] [/ M text]

Description:

The tool allows the user to select an item from the selection list and return the index of the selected item.

Parameter list:

/ C choices specifies the list of options to create. The default list is "YN".

/ N hides the list of options in the prompt. Prompt that the previous message is displayed

The option is still enabled.

/ CS allows you to select case-sensitive options. By default, this tool

Regardless of case.

The number of seconds paused before / T timeout makes the default selection. Acceptable values are from 0

To 9999. If 0 is specified, there will be no pause, the default option

You'll get a choice.

/ D choice specifies the default option after nnnn seconds. Characters must be in use / C selection

Item; at the same time, nnnn must be specified with / T.

/ M text specifies the message to be displayed before the prompt. If not specified, the tool only

Displays prompts.

/? Displays a help message.

Note:

The ERRORLEVEL environment variable is set to the key index selected from the selection set. The first selection listed

The option returns 1, the second option returns 2, and so on. If the key pressed by the user is not a valid selection

The tool emits a warning sound. If the tool detects an error status, it returns 255

ERRORLEVEL value. If the user presses the Ctrl+Break or Ctrl+C key, the tool returns 0

The ERRORLEVEL value of the When using the ERRORLEVEL parameter in a batch program, lower the parameter

Arrange in order.

Example:

CHOICE /?

CHOICE / C YNC / M "press Y for confirmation, N for confirmation, or C for cancellation."

CHOICE / T 10 / C ync / CS / D y

CHOICE / C ab / M "Please select a for option 1 and b for option 2."

CHOICE / C ab / N / M "Please select a for option 1 and b for option 2."

If I run the command: CHOICE / C YNC / M, press Y to confirm, N to confirm, or C to cancel.

The screen displays:

Press Y for confirmation, N for confirmation, or C for cancellation. [Y,N,C]?

Example: the contents of test.bat are as follows (note that when you use if errorlevel to judge the return value, you should arrange the return value from high to low):

@ echo off

Choice / C dme / M "defrag,mem,end"

If errorlevel 3 goto end

If errorlevel 2 goto mem

If errotlevel 1 goto defrag

: defrag

C:\ dos\ defrag

Goto end

: mem

Mem

Goto end

: end

Echo good bye

After this batch is run, "defrag,mem,end [DJM me]?" will be displayed, and the user can select d me, and then the if statement will judge according to the user's choice. D means to execute the program segment labeled defrag, m means to execute the program segment labeled mem, e means to execute the program segment labeled end, and each program segment finally jumps the program to the end label with goto end, and then the program will display good bye. The batch run ends.

Fourth, the for loop command, as long as the conditions are met, it will execute the same command multiple times.

Syntax:

Execute a specific command for each file in a set of files.

FOR% variable IN (set) DO command [command-parameters]

% variable specifies a parameter that can be replaced by a single letter.

(set) specify a file or group of files. You can use wildcards.

Command specifies the commands to be executed on each file.

Command-parameters

Specify parameters or command line switches for a specific command.

For example, there is a line in a batch file:

For% c in (* .bat * .txt) do type% c

The command line displays the contents of all files in the current directory with bat and txt extensions.

Batch processing example

1. IF-EXIST

1)

First, use notepad to create a test1.bat batch file in C:\, with the following contents:

@ echo off

IF EXIST\ AUTOEXEC.BAT TYPE\ AUTOEXEC.BAT

IF NOT EXIST\ AUTOEXEC.BAT ECHO\ AUTOEXEC.BAT does not exist

Then run it:

C:\ > TEST1.BAT

If an AUTOEXEC.BAT file exists in C:\, its contents will be displayed, and if it does not exist, the batch will prompt you that the file does not exist.

2)

Then create a test2.bat file with the following contents:

@ ECHO OFF

IF EXIST\ 1 TYPE\% 1

IF NOT EXIST\% 1 ECHO\% 1 does not exist

Execute:

C:\ > TEST2 AUTOEXEC.BAT

The result of running the command is the same as above.

Description:

(1) IF EXIST is used to test the existence of files in the format of

IF EXIST [path + File name] command

(2)% 1 in the test2.bat file is a parameter, and DOS allows you to pass 9 batch parameter information to the batch file, which is% 1% 9 (% 0 represents the test2 command itself), which is a bit like the relationship between arguments and formal parameters in programming.% 1 is a formal parameter and AUTOEXEC.BAT is an actual parameter.

3) further, create a file called TEST3.BAT, which reads as follows:

@ echo off

IF "% 1" = = "A" ECHO XIAO

IF "% 2" = = "B" ECHO TIAN

IF "% 3" = = "C" ECHO XIN

If you run:

C:\ > TEST3 A B C

The screen displays:

XIAO

TIAN

XIN

If you run:

C:\ > TEST3 A B

It will appear on the screen

XIAO

TIAN

During the execution of this command, DOS assigns an empty string to the parameter% 3.

2 、 IF-ERRORLEVEL

Create a TEST4.BAT with the following contents:

@ ECHO OFF

XCOPY C:\ AUTOEXEC.BAT D:\

IF ERRORLEVEL 1 ECHO file copy failed

IF ERRORLEVEL 0 ECHO successfully copied the file

Then execute the file:

C:\ > TEST4

If the file copy is successful, the screen displays "copy file successfully", otherwise "file copy failed" is displayed.

IF ERRORLEVEL is used to test the return value of its last DOS command, note that it is only the return value of the previous command, and the return value must be judged in order from highest to lowest.

So the following batch file is incorrect:

@ ECHO OFF

XCOPY C:\ AUTOEXEC.BAT D:\

IF ERRORLEVEL 0 ECHO successfully copied the file

IF ERRORLEVEL 1 ECHO could not find the copy file

IF ERRORLEVEL 2 ECHO user aborts copy operation through ctrl-c

IF ERRORLEVEL 3 ECHO preset error prevents file copy operation

IF ERRORLEVEL 4 disk write error during ECHO copy

Regardless of whether the copy is successful or not, the following:

Copy file not found

The user aborts the copy operation through ctrl-c

Preset error prevents file copy operation

Write disk error during copy

Will be displayed.

Here are the return values of several commonly used commands and what they represent:

Backup

0 backup successful

1 backup file not found

2 File sharing conflicts prevent backups from being completed

3. Users abort backup with ctrl-c

4 the backup operation was aborted due to a fatal error

Diskcomp

0 disk is the same.

One set is different.

2 the user aborts the comparison operation through ctrl-c

3 the comparison operation is aborted due to a fatal error

4 comparison of preset error abort

Diskcopy

0 disk copy operation succeeded

1 non-fatal disk read / write error

2 the user ends the copy operation through ctrl-c

3 abort the copy of the disk due to a fatal processing error

4 preset error prevents copy operation

Format

0 formatted successfully

3 the user aborts the formatting process through ctrl-c

4 the format was aborted due to a fatal processing error

5 prompting "proceed with format (yzone)?" The next user types n to end.

Xcopy

0 successfully copied the file

1 copy file not found

2 the user aborts the copy operation through ctrl-c

4 preset error prevents file copy operation

5 disk writing error during copy

3. IF STRING1 = = STRING2

Create a TEST5.BAT. The file content is as follows:

@ echo off

IF "% 1" = = "A" FORMAT A:

Execute:

C:\ > TEST5 A

The content of whether to format the A: disk appears on the screen.

Note: in order to prevent the argument from being empty, it is common to enclose the string in double quotes (or other symbols, note that you cannot use reserved symbols).

For example: if [% 1] = = [A] or if% 1

5 、 GOTO

Create a TEST6.BAT. The file content is as follows:

@ ECHO OFF

IF EXIST C:\ AUTOEXEC.BAT GOTO _ COPY

GOTO _ DONE

: _ COPY

COPY C:\ AUTOEXEC.BAT D:\

: _ DONE

Note:

(1) the colon ":" before the label is the ASCII character. There can be no space between the colon and the label.

(2) the naming rules of labels are the same as those of file names.

(3) DOS supports labeling with a maximum of eight characters. When it is impossible to distinguish between two labels, it will jump to the nearest label.

6 、 FOR

Create C:\ TEST7.BAT. The file content is as follows:

@ ECHO OFF

FOR% C IN (* .BAT * .TXT * .SYS) DO TYPE% C

Run:

C:\ > TEST7

After execution, the contents of all files under the root directory of C: disk with the extensions of BAT, TXT, and SYS will be displayed (excluding hidden files).

The above is all the contents of the article "what are the skills for writing the necessary command parameters for batch processing". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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