China DOS Union

I'm no good at anything else, but sometimes I get sudden ideas.
Please test the following code, so as to inspire everyone to dig into the potential of certain commands.

@echo off

Title Calculating String Length

set /p string=Please enter a string: 



REM ""%string%" is for compatibility with input containing spaces



echo "%string%">%temp%\temp.txt

echo eof>>%temp%\temp.txt

for /f "delims=:" %%i in ('findstr /o /c:"eof" %temp%\temp.txt') do set /a len=%%i-4

echo String length:%len%

pause

What you get is not the string length, but... the byte count...

If it's Chinese characters...

PS: If you're using the file size method, it seems you can use for's %~zI

Can't really count as a new method, right? People brought up the offset method a long time ago.

@echo off

set str=abc

for /f "skip=1 delims=:" %%a in ('^(echo "%str%"^&echo.^)^|findstr /o ".*"') do set /a length=%%a-5

echo %length%

If you're generating a temporary file, then just use for's %~zI directly, otherwise use the method from post #3

If you also calculate Chinese characters by offset, you'll get the wrong result, hehe.

@echo off

set str=我是abc

set length=0

:begin

set char=%str:~0,1%

set /a length+=1

set str=%str:~1%

if "%str%" equ "" (

  echo %length%

  goto :eof

) else (

  goto :begin

)

But I did think of this independently. I didn't know someone had already brought it up. What a pity, I originally thought it was the first of its kind.

If I'd known earlier, I wouldn't have taken it out and made a fool of myself.

By the way, can anyone give some detailed examples of findstr? List each parameter, especially things in regular expressions like $ and \X and the like. I really haven't seen any concrete examples.

TO 6

This is the FINDSTR usage info I collected. It's very helpful, let's learn it together!~

Basic usage of FINDSTR regular expressions

Code:

1.findstr . 2.txt or Findstr "." 2.txt  

Search for any character in file 2.txt, excluding null characters or blank lines

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2.findstr .* 2.txt or findstr ".*" 2.txt

Search for any character in file 2.txt, including blank lines and null characters

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3.findstr "" 2.txt

Search in file 2.txt for strings or lines containing digits 0-9

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4.findstr "" 2.txt

Search in file 2.txt for strings or lines containing any letters

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5.findstr "" 2.txt

Search in file 2.txt for strings or lines containing the letters a b c e z y

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6.findstr "" 2.txt

Search in file 2.txt for strings containing lowercase characters a-f and l-z, but not the letters g h I j k.

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7.findstr "MY" 2.txt

In file 2.txt it can match MahY, MbiY, MahY, etc.....

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8. The use of the symbols ^ and $

^ indicates the beginning of a line, "^step" only matches the first word in "step hello world"

$ indicates the end of a line, "step$" only matches the last word in "hello world step"

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9.finstr "" 2.txt

If it is a purely numeric string or line, then it will be filtered out, for example a string like 2323423423. But if it is in a form like 345hh888 then it won't work.

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10.findstr "" 2.txt

Same as above, if it is a purely alphabetic string or line, then it will be filtered out, for example characters like sdlfjlkjlksjdklfjlskdf. But if it is in a form like sdfksjdkf99999, mixed with digits, then it won't work.

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11.The role of the * sign

As already mentioned above, ".*" means the search condition is any character. The role of * in regular expressions is not any character, but indicates the repetition count of the character or expression on the left side. * indicates the repetition count is zero or more times.

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12.findstr "^*$" 2.txt

This matches purely numeric text that is found, for example 234234234234. If it is 2133234kkjl234 then it gets filtered out.

Findstr "^*$" 2.txt

This matches purely alphabetic text that is found, for example sdfsdfsdfsdf. If it is 213sldjfkljsdlk then it gets filtered out.

If there is no * sign in the search condition, that means the search condition on the left side is not repeated, that is  , then it can only match the first character of the string, and only this one character, because there is the restriction of beginning and end of line. With "^$", if the first character is a digit then it matches, if not then it is filtered out. If the string is 9 then it matches, but if it is 98 or 9j and the like then it won't work.

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13. The role of the "\<…\>" expression

This means searching exactly for a string. \<sss indicates the starting position of the word, and sss\> indicates the ending position of the word.

echo hello world computer|findstr "\<computer\>" works in this form

echo hello worldcomputer|findstr "\<computer\>" in this form won't work. What it wants to find is the string "computer", so that won't do.

echo hello worldcomputer|findstr ".*computer\>" this way it can match

For reference on the function of symbols in CMD/DOS
http://www.cn-dos.net/forum/viewthread.php?tid=30985&fpage=4

If you still don't understand, you can post the findstr command you saw, and naturally someone will explain it, hehe.

OP, I just looked at your program for calculating character length, and there's a question: why do you subtract 4 at the end, and not 3? eof is only three characters. Thanks for clearing that up for me.

Subtract 4, namely: two double quotation marks, one newline character \n, and one text end marker eof

Thanks, brother above