In an attempt to reuse code I am trying to use dynamic variables to test a condition but am unable to get the result I need. I'm using delayed expansion.
1 Outside the for loop:
2 set "H_HEADER=FALSE"
3 set "SUB_TRANSTYPE=#"
4
5 Inside the for loop:
6 set "SUB_TRANSTYPE=!FULL_LINE:~0,1!"
7 if !SUB_TRANSTYPE!==H (
8 echo sub_transtype_header is !!SUB_TRANSTYPE!_HEADER!
9 )
Line 6 sets SUB_TRANSTYPE to H
Line 8 prints H_HEADER to console but I want it to print FALSE (the value of H_HEADER)
I've messed around with escape characters but can't get this to work. Help!
Line 6 should be:
set "SUB_TRANSTYPE=!FULL_LINE:~0,1!"
Line 7 should be:
if !SUB_TRANSTYPE!==H (
Line 8 should be:
for /F %%A in ("!SUB_TRANSTYPE!") do echo sub_transtype_header is !%%A_HEADER!
This type of management is fully described at this answer.
if !SUB_TRANSTYPE!==H (
CALL echo sub_transtype_header is %%!SUB_TRANSTYPE!_HEADER%%
)
note that you have a = missing from the == operator.
This executes the echo in a subshell.
To interpret the value in an if statement, use
call set "someothervariable=%%!SUB_TRANSTYPE!_HEADER%%"
if "!someothervariable!"=="value" (
Related
This question already has answers here:
Why is no string output with 'echo %var%' after using 'set var = text' command in cmd? [duplicate]
(2 answers)
Closed 2 years ago.
#echo off
set a[0] = 1
echo %a[0]%
When I try to run this, all I get is: "ECHO is off" and not a[0]. When I try to run it with echo on, all it returns is that echo is on. What do I need to change so that it only echoes the value of a[0]?
Remove the white spaces around the assignment.
Instead of ,
set a[0] = 1
Use
set a[0]=1
The script would look like .,
#echo off
set a[0]=1
echo %a[0]%
I am making an experimental program in batch for a simple chatting interface. In this one, I made a function where if there is the word r placed in chat, it ignores it and just redisplays the text file again. It works fine if I put r and it just refreshes, and if I put one word it works fine, but if I put a word and a space and another word, it breaks and shows the following error:
Chat(Put r for refresh):hey hi
hi was unexpected at this time.
Does anyone know how to fix this? Thanks.
Code:
#echo off
cls
cd %USERPROFILE%\Desktop\Chat
for /f "delims=" %%A in (chat.txt) do (
set %%A
)
echo %chatt%
echo %chatp%
echo %chatn%
cd %USERPROFILE%\Desktop\Chat\Servers\%chatt%
:1
cls
type %chatn%.chat
set /p in=Chat(Put r for refresh):
if %in% == r goto 1
echo %chatp%: %in%>>%chatn%.chat
goto 1
The usual way to deal with spaces in a string variables contents is to wrap it in quotes. This is the case here. When you use the variables contents with %in% the contents are inserted verbatim, so the suspect line would look like this:
if hey hi == r goto 1
It starts off okay if hey but then instead of seeing a comparison operator like == it sees hi and chokes. So wrap it all in quotes:
if "%in%" == "r" goto 1
That way it will be interpreted like
if "hey hi" == "r" goto 1
and the bat engine will know that "hey hi" should be treated as one entity.
echo %time:~-5% returns a 5-character string, such as
18.09
However, i cannot seem to set that string to a variable:
set start = %time:~-5%
echo %start%
returns
10:07:18.09
what's simple way to get those last 5 chars into a variable?
thx
Windows doesn't like space next to =. So try this ...
set start=%time:~-5%
echo %start%
Windows user defined environment variable names can contain any character except =.
Special characters can be included by escaping them. A simpler method is to simply enclose the entire SET expression within quotes. For example:
set "A weird & "complex" variable=My value"
set A weird ^& "complex" variable=My value
Both expressions above give the same result. The variable name is A weird & "complex" variable and the value is My value
The IF DEFINED construct is used to test if a variable is defined. Quotes don't work for this test, special characters in the name (including quotes) must be escaped.
set "A&B=value"
if defined A^&B echo This works
if defined "A&B" echo This does not work
The above escaped test works just fine. The quoted test does not work
But how can I test if a variable containing spaces exists?
set "A B=value"
if defined A^ B echo this does not work!
It seems like the above should work, but it doesn't!
I'm looking for an answer that does NOT involve expanding the variable using %A B% or !A B!
Interessting question (I love this syntax base questions).
Obviously you know how to check it with delayed expansion and also FOR-parameters works.
#echo off
setlocal
set "AAA BBB=value"
set ""AAA BBB"="
set "AAA="
for %%a in ("AAA BBB") do if defined %%~a echo FOR: This works
setlocal EnableDelayedExpansion
set "varname=AAA BBB"
if defined !varname! echo Delayed: This works
if defined %varname% ( echo percent: Never comes here
) ELSE ( echo percent: Never comes here ? )
if defined AAA^ BBB ( echo escape1: Never comes here
) ELSE ( echo escape1: fails )
set AAA=Hello
if defined AAA^ BBB (
echo escape2: It only test for AAA the BBB will be "removed"
) ELSE ( echo escape2: fails )
set "space= "
if defined AAA!space!BBB echo inject space: This works
if defined "AAA BBB" (echo Quote1: Never comes here
) ELSE ( echo Quote1: Fails )
set ""AAA BBB"=value"
if defined "AAA BBB" echo Quote2: This works, it checks for "AAA BBB" with quotes
In my opionion, in the escape2 example the parser first split the line into tokens this way:
<if> <defined> <AAA BBB> <echo ....
But at the execution time of the if defined it rescan the <AAA BBB> token so it only gets the AAA.
You can't inject a second escape like AAA^^^ BBB as this only searches for the variable named AAA^
I can't see a solution without delaying/FOR, as the escaping of the space always fails.
EDIT: It can also be solved with SET <varname>
The solution of ijprest uses the SET command to test the variable without the need of escaping the varname.
But it also shows interessting behaviour with spaces inside and at the end of a varname.
It seems to follow these rules:
SET varname searches for all variables beginning with varname, but first it removes all characters after the last space character of varname, and it removes all leading spaces.
So you can't search for variables with beginning with space (but it is also a bit tricky to create such a varname).
The same behaviour is also active if the variablename is enclosed into quotes, but then exists one more rule.
First remove all characters after the last quote, if there are at least two quotes.
Use the text inside of the quotes, and use the "space"-rule.
Sample.
set " abc def ghi" junk junk
*** 1. removes the junk
set " abc def ghi"
*** 2. removes the quotes
set abc def ghi
*** 3. removes all after the last space, and the trailing spaces
set abc def
*** Search all variables beginning with abc def
I also love this sort of question! :)
Here's another possible solution I came up with... using SET itself to test the existence, and using the ERRORLEVEL result:
set "A B=foo"
set A B >nul 2>nul&& echo 1. This works
set "A B ">nul 2>nul&& echo 2. This works
set "A weird & "complex" variable=foo"
set A weird ^& "complex" variable >nul 2>nul&& echo 3. This works
set "A weird & "complex" variable ">nul 2>nul&& echo 4. This works
Note that this only works if your variables are unique in the sense that no variable name is the prefix of another one. Otherwise you risk false positives, as SET's default behavior is to show all variables that start with the parameter you pass. If this could be the case, you could filter the results with findstr:
set "A B="
set "A B C=foo"
set "A B ">nul 2>nul&& echo 5. Failed (false positive)
set "A B "|findstr /B /L /C:"A B=" >nul||echo 6. This works (no false positive)
Also, the single trailing space after the variable name seems to be required. Without it, SET often mis-parses the input. Bizarrely, if you add an extra space between the "2>nul" and "&&" in case #3 it stops working (unless you remove the space before ">nul")... weird.
The other way is to reassign it to another variable (one without spaces) and test that. See here:
rem Prepare ONLY variable 'a b'
set "a b=123"
echo [a b]=%a b%
rem This will ouput: [a b] is defined
set var=%a b%
if defined var (
echo [a b] is defined
) else (
echo [a b] is not defined
)
rem This will output: [c d] is not defined
set var=%c d%
if defined var (
echo [c d] is defined
) else (
echo [c d] is not defined
)
I do it by defining a flag as TRUE if needed...
rem /* sample code */
set VAR_SET=
if <some condition> set VAR_SET=TRUE&set VAR=this data has spaces
rem /* test for VAR_SET using 'if defined' */
if defined VAR_SET (
rem /* do something with the other data in the variable %VAR% */
)
rem /* clear the flag */
set VAR_SET=
I want to assign the alpha numeric value to one variable in Batch scripting.
I tried following one but getting error.
setlocal
set test = \765514e2aad02ca658cc56cdb7884947 *E:\\test1
echo %test%
endlocal
Error:
C:\Users\bgannu>setlocal
C:\Users\bgannu>set test = \765514e2aad02ca658cc56cdb7884947 *E:\\test1
C:\Users\bgannu>echo 0
0
C:\Users\bgannu>endlocal
The syntax for set is set [[/a [expression]] [/p [variable=]] string]
The = has to be directly after your variable so you need to change:
set test = \765514e2aad02ca658cc56cdb7884947 *E:\\test1
to:
set test=\765514e2aad02ca658cc56cdb7884947 *E:\\test1
Otherwise your variable name would have a space at the end. You can easily try this out:
> set bar = foo
> echo %bar%
%bar%
> echo %bar %
foo
Note that both the variable name and its content got a space.
Lose the /A. the /A is used for arithmetic.
C:\test>set var=\765514e2aad02ca658cc56cdb7884947 *E:\\test1
C:\test>echo %var%
\765514e2aad02ca658cc56cdb7884947 *E:\\test1