China DOS Union

Hehe, a new discovery: There are two files on my desktop, "New Batch.bat" and "New Batch(2).bat". The code of the former is

@echo off







dir/b|findstr  /i  /v "%~0"|findstr /n .*



pause

The code of the latter is

@echo off







dir/b|findstr  /i  /v "%~n0.bat"|findstr /n .*



pause

The result of running the former is:


The result of running the latter is:


It's like this: The former can recognize the latter, but the latter can't recognize the former. Interesting, right

Actually, this is an important feature of the `findstr "string1 + space + string2 + space + string3 + space……"` statement, that is: as long as any string separated by spaces in the quotes is found, findstr considers that a matching string is found. For example, the following code:

@echo off

findstr "abc 123 xyz" test.txt

pause

Test the content of test.txt with abc, 123, xyz or their combinations like abc123, 123xyz, etc., and you will find that the execution result of the above code always displays the content of test.txt.

If you want to find the string "abc 123 xyz" (excluding the quotes at the front and back), you need to add the `/c:` switch, and it becomes `findstr /c:"abc 123 xyz" test.txt`.

[ Last edited by namejm on 2007-1-28 at 10:27 AM ]

Haha... This is fun~ :)

After turning on @echo on, it was found to be related to Findstr:

Run the following code (file name: "New Batch(2).bat"):

@echo on

::off



dir/b|findstr  /i  /v "%~n0.bat"|findstr /n .*



pause

When @echo on is enabled and the code is run:

dir/b | findstr  /i  /v "New Batch(2).bat"  | findstr /n .*

　……

　……

It was found that the file name "New Batch(2).bat" searched by Findstr above is a file name with spaces in the middle, and this file name with spaces is also the string to be searched by Findstr.

However, the characteristic of Findstr is that "string A string B" Although they are within the same quote range, the characteristic of Findstr is that it will be understood to search for both conditions at the same time, that is, as long as it contains "string A" or contains "string B", then it meets the target that Findstr wants to search.

And the file name to be searched in the above quotes happens to have spaces, so Findstr understands it as: find "New" or the string containing "Batch(2).bat" meets the condition, plus /V to filter out the target, and the file names of these two batches both contain The retrieval success condition of "New" is filtered out.

After renaming the file name and removing the spaces in the middle, the search is correct, and the above factor is inferred~ :)

Thanks to two's wonderful explanations. It seems that to make the command execute successfully, we should ensure that the batch file name contains as few spaces as possible.

[ Last edited by ccwan on 2007-1-28 at 11:24 PM ]

Names with spaces are also okay. The solutions are:
1. As I said on floor 17, you need to add the /c: switch to findstr;
2. Replace findstr with find.

namejm's explanation is really good. Got it! Thanks

I can sense everyone's fascination with batch processing... They can discuss like this for a little problem. I like this atmosphere more and more.
Unfortunately, for now I can only be a bystander to feel your passion and get excited. But I can't participate in the discussion yet.
I will work hard to become one of you..
Thanks you, ccwan, namejm, redtek

[ Last edited by g4rr on 2007-1-28 at 05:54 PM ]

Originally posted by g4rr at 2007-1-28 17:50:
namejm's explanation is really good. I understand! Thank you

I can feel everyone's fascination with batch processing... We can discuss such small issues like this. I like this atmosphere more and more.
Unfortunately, for now I only ...

The same as above.................................

Leave a mark, will study later...

set/a a=%random%%%20+1
for /f "tokens=1,2 delims=: %%i in ('dir/b ^|findstr /n .*') do (if "%%i"=="%a%" start %%~fsj)

Does variable delay not need?
Already understood. Thank you lxmxn

[ Last edited by wudixin96 on 2007-4-4 at 01:49 AM ]

Haha, not bad! All experts