batch_循环文件中的行，并检查行是否以"#“开头

Question

嗨，伙计，我有一个windows外壳的脚本.bat。我有这个文件：

line
line
#line
line
#line

我想逐行阅读文件，如果一行以"#“开头，我不做任何其他操作，我会做一些详细说明。如何做到这一点呢？我发布了伪代码

while (s=readline()!=null)
  {

  if(s.charat(0)!='#')
     do some elaboration
   }

Answer 1

基于你的伪代码，这是你想要的吗？

@echo off
setlocal enabledelayedexpansion
for /f "delims=" %%i in (file.txt) do (
    set line=%%i
    if !line:~0,1! equ # (
        ::Your code here:
    )
)

注意，您需要用要迭代的文件替换file.txt。

Answer 2

@ECHO OFF
SETLOCAL
:: first way - findstr
FOR /f "delims=" %%i IN (yourfile.txt) DO (
 ECHO %%i|FINDSTR /b "#" >NUL
 IF ERRORLEVEL 1 (ECHO non-#  : %%i) ELSE (ECHO #START : %%i)
)
ECHO ====== first way ===========
ENDLOCAL
SETLOCAL enabledelayedexpansion
:: second way - substring with delayedexpansion
FOR /f "delims=" %%i IN (yourfile.txt) DO (
 SET line=%%i
 if "!line:~0,1!"=="#" (ECHO #START : %%i) ELSE (ECHO non-#  : %%i)
)
ECHO ====== second way ===========
ENDLOCAL
SETLOCAL
:: third way -without delayedexpansion substringing and flagging in subroutine
FOR /f "delims=" %%i IN (yourfile.txt) DO (
 SET line=%%i
 CALL :test
 IF DEFINED line (ECHO non-#  : %%i) ELSE (ECHO #START : %%i)
)
ECHO ====== third way ===========
ENDLOCAL

GOTO :eof

:test
IF "%line:~0,1%"=="#" SET "line="
GOTO :eof

这里有三种方式-取决于进一步的细节。请注意，第三种方式使用IF DEFINED或IF ERRORLEVEL对变量的运行时值起作用的特性，而不是对解析时值起作用

Answer 3

这是解决这个问题的最快方法：

for /F "eol=# delims=" %%a in (file.txt) do (
   echo Line that not start with #: %%a
)