在批处理中使用特殊字符读取文件 [英] Reading a file with special characters in Batch

问题描述

如何在批处理中读取和解析包含特殊字符的文件？我有一个名为test.txt的文本文件，只有 foo !!! bar 和一个批处理文件：

 @echo off 
 setlocal enabledelayedexpansion enableextensions 
 
 FOR / Ftokens = * delims =%% a IN（.\test.txt） DO（
 echo未加引号是%% a 
引用是%% a
 setmyVar = %% a
 echo myVar is still！myVar！or！ myVar！
）
 exit / b 0 
  

我想和期待它以某种方式输出 foo !!! bar ，但是输出：

 无引号的是foobar 
引用是foobar
 myVar仍然是foobar或foobar
  

当然，我可以只用类型t​​est.txt ，但是我想处理文件的每一行。

您的问题是批解析器的一个副作用，它是阶段。

FOR参数在延迟扩展阶段扩展之前被扩展。

但是当 %% a foo !! bar ，那么延迟的扩展将删除感叹号，如 !! 您需要切换延迟扩展，如 %% a 的扩展只有禁用延迟扩展才是安全的。

  @echo off 
 setlocal DisableDelayedExpansion enableextensions 
 
 FOR / Ftokens = * delims =%% a IN（.\test.txt）DO（
 echo未加引号是%% 
引用是%% a
 setmyVar = %% a 
 
 setlocal enabledelayedexpansion 
 echo myVar is still！myVar！or！myVar！
 endlocal 
）
  pre> 
 
 
你也可以看看如何解析CMD.EXE ...  
 
How do I read and parse a file with special characters in Batch? I have a text file named test.txt with just foo!!!bar and a batch file with this:
@echo off
setlocal enabledelayedexpansion enableextensions

FOR /F "tokens=* delims=" %%a IN (.\test.txt) DO (
    echo Unquoted is %%a
    echo Quoted is "%%a"
    set "myVar=%%a"
    echo myVar is still !myVar! or "!myVar!"
)
exit /b 0
I want and expect it to output foo!!!bar somehow, but this outputs:
Unquoted is foobar
Quoted is "foobar"
myVar is still foobar or "foobar"
Of course I can just type test.txt, but I want to process each line of the file.
解决方案
Your problem is a side effect of the batch parser and it's phases.  

The FOR parameters are expanded just before the delayed expansion phase would be expand.

But when %%a is foo!!bar, then the delayed expansion would remove the exclamation marks, as !! isn't a valid variable expansion.

You need to toggle the delayed expansion, as expanding of %%a is only safe with disabled delayed expansion.  
@echo off
setlocal DisableDelayedExpansion enableextensions

FOR /F "tokens=* delims=" %%a IN (.\test.txt) DO (
    echo Unquoted is %%a
    echo Quoted is "%%a"
    set "myVar=%%a"

    setlocal enabledelayedexpansion 
    echo myVar is still !myVar! or "!myVar!"
    endlocal
)
You could also look at How does the CMD.EXE parse...

                        
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