[batch dos-cmd command - summary and summary] - output / display command - echo

One 、 Show echo On / off state of

echo： Nothing is added after the instruction

Two 、 adjustment echo On / off state of

Open a new one at a time cmd window , Will be opened by default echo state .

Let's try to close it first .

echo off： close echo The state of

 

Open it again .

echo on： open echo The state of

  It can also be seen from the above , It will be hidden when it is closed cmd The current working path of the window .

in addition , If you put dos The command is placed in a bat In the document , Prior to echo off , The current working path will not be displayed later , It will not display all the instructions that have been executed .

  above bat The results of file execution are as follows , After execution echo off after ,echo 234、pause These two instructions disappear .

3、 ... and 、 Show / Print / Output the result of execution or operation

echo [ data ]： Data can be constant , It can also be a variable , Like system variables .

Common system variables are shown in the following table ： 

Variable name	Range	describe
%ALLUSERSPROFILE%	Local	return “ All user profiles ” The location of .
%APPDATA%	Local	Returns where the application stores data by default .
%CD%	Local	Returns the current directory string .
%CMDCMDLINE%	Local	Return to start the current  Cmd.exe The exact command line for .
%CMDEXTVERSION%	System	Returns the current “ Command handler extension ” Version number of .
%COMPUTERNAME%	System	Returns the name of the computer .
%COMSPEC%	System	Returns the exact path of the command line interpreter executable .
%DATE%	System	Return current date . Use with date /t Command the same format . from Cmd.exe Generate . of date Command details , see also  Date.
%ERRORLEVEL%	System	Returns the error code of the previous command . Errors are usually represented by nonzero values .
%HOMEDRIVE%	System	Returns the local workstation drive letter connected to the user's home directory . Set based on the home directory value . The user home directory is in “ Local users and groups ” Specified in the .
%HOMEPATH%	System	Return the full path of the user's home directory . Set based on the home directory value . The user home directory is in “ Local users and groups ” Specified in the .
%HOMESHARE%	System	Return the network path of the user's shared home directory . Set based on the home directory value . The user home directory is in “ Local users and groups ” Specified in the .
%LOGONSERVER%	Local	Returns the name of the domain controller that verifies the current login session .
%NUMBER_OF_PROCESSORS%	System	Specifies the number of processors installed on the computer .
%OS%	System	Returns the operating system name .Windows 2000 Will display the operating system as Windows NT.
%PATH%	System	Specify the search path for the executable .
%PATHEXT%	System	Returns a list of file extensions considered executable by the operating system .
%PROCESSOR_ARCHITECTURE%	System	Return the chip architecture of the processor . value ：x86 or IA64（ be based on Itanium）.
%PROCESSOR_IDENTFIER%	System	Return processor description .
%PROCESSOR_LEVEL%	System	Returns the model number of the processor installed on the computer .
%PROCESSOR_REVISION%	System	Returns the version number of the processor .
%PROMPT%	Local	Returns the command prompt settings for the current interpreter . from Cmd.exe Generate .
%RANDOM%	System	return 0 To 32767 Any decimal number between . from Cmd.exe Generate .
%SYSTEMDRIVE%	System	Return contains Windows Server operating system root directory （ The root directory of the system ） The driver of .
%SYSTEMROOT%	System	return Windows Location of the server operating system directory .
%TEMP% and %TMP%	Systems and users	Returns the default temporary directory used by the application available to the currently logged in user . Some applications need to TEMP, Other applications need TMP.
%TIME%	System	Return current time . Use with time /t Command the same format . from Cmd.exe Generate . of time Command details , see also  Time.
%USERDOMAIN%	Local	Returns the name of the domain containing the user account .
%USERNAME%	Local	Returns the name of the currently logged in user .
%USERPROFILE%	Local	Returns the location of the current user's profile .
%WINDIR%	System	Returns the location of the operating system directory .

 （1） Print a constant

（2）  Print a system variable