[文本处理] [已解决]求助批处理if语句内拼接字符串为什么不行？

hardstone

set M=@
if "1" == "1" (
    echo !!!!!!!!!!
    echo 0%M%
    set "x=0%M%"
    
    echo %x%?
    :: why it echo just one 
    echo !!!!!!!!!!
)
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echo出的结果是?而不是0@?

77七

@echo off
set M=@
if "1" == "1" (
	echo !!!!!!!!!!
	setlocal enabledelayedexpansion
	echo 0!M!
	set "x=0!M!"
	
	echo !x!?
	endlocal
	rem why it echo just one 
	echo !!!!!!!!!!
)
pause
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参考：   [教程汇总]批处理中的变量延迟扩展、变量嵌套

ShowCode

回复 1# hardstone

@echo off
setlocal enabledelayedexpansion
set "M=@"
if "1" == "1" (
    echo ----------
    echo 0%M%
    set "x=0%M%"
    echo !x!
    echo ----------
)
pause
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aloha20200628

回复 1# hardstone

除了采用变量延迟应对 ‘预处理’，还可采用call+%%v%%方法应对 ‘预处理’ ...

@echo off 
set M=@
if "1" == "1" (
    echo !!!!!!!!!!
    echo 0%M%
    call set "x=0%%M%%"
    call echo %%x%%?
    echo !!!!!!!!!!
)
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hardstone

谢谢大佬们解答！