@ 表示“不要将命令回显到控制台”。命令回显由echo on 和echo off 控制。 Echo 默认情况下ON，因此命令@echo off 表示“关闭echo，但不< code>echo 将此行发送到控制台。
因此，一旦执行 @echo off ，就无需在命令之前添加 @
。第三个 echo 语句，您已指定targAtname，未定义，因此报告没有显示该项目的
!，而是 % 。意味着“变量在运行时的值，而不是在解析时的值”，并且实际上仅适用于调用更改变量的循环的语句，例如 for 循环，但是正如aschipfl所指出的，它很有用克服 echo 语句中的特殊字符影响
让我们检查一下批处理对于一次分配的作用：
@set TARGETPATH=%~p1
批处理替换第一个stpath 部分。 > %~p1 的参数，因此实际执行的命令是
@set TARGETPATH=A & B\
将 A 分配给 targetpath，然后尝试执行 B\< /code> 因此出现错误消息。
在字符串赋值上，使用语法
set "TARGETPATH=%~p1"
引号可以防止命令行上出现杂散尾随空格，并且还可以解决大多数特殊字符问题。
顺便说一句：
set target
将echo名称以target开头的所有变量
Just a few tips:
@ means "do not echo the command to the console". Command-echoing is controlled by echo on and echo off. Echo is ON by default, so the command @echo off means "Turn echo off, but do not echo this line to the console.`
Hence, once an @echo off is executed, there is no need to put @ before commands.
In your third echo statement, you have specified targAtname, which is undefined, hence the report shows nothing for that item.
! in place of % means "the value of the variable as it is at run-time, not at parse-time" and is really only applicable where a statement invokes a loop which changes the variable, like a for loop, but as aschipfl has pointed out, it comes in useful to overcome the special-characters effects in an echo statement.
Let's examine what batch does for one assignment:
@set TARGETPATH=%~p1
Batch substitutes the path part of the 1st parameter for %~p1 so the actual command executed is
@set TARGETPATH=A & B\
hence it assigns A to targetpath and then attempts to execute B\ hence the error message.
On a string assignment, it is standard practice on SO to use the syntax
set "TARGETPATH=%~p1"
The quotes protect against stray trailing spaces on the command line, and will also cure most problems with special characters.
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只是一些提示：
@表示“不要将命令回显到控制台”。命令回显由echo on和echo off控制。Echo默认情况下ON，因此命令@echo off表示“关闭echo，但不< code>echo 将此行发送到控制台。因此，一旦执行
@echo off，就无需在命令之前添加@。第三个
echo语句，您已指定targAtname，未定义，因此报告没有显示该项目的!，而是
%。意味着“变量在运行时的值，而不是在解析时的值”，并且实际上仅适用于调用更改变量的循环的语句，例如for循环，但是正如aschipfl所指出的，它很有用克服echo语句中的特殊字符影响让我们检查一下批处理对于一次分配的作用：
批处理替换第一个stpath 部分。 > %~p1 的参数，因此实际执行的命令是
将
A分配给targetpath，然后尝试执行B\< /code> 因此出现错误消息。在字符串赋值上，使用语法
引号可以防止命令行上出现杂散尾随空格，并且还可以解决大多数特殊字符问题。
顺便说一句：
将
echo名称以target开头的所有变量Just a few tips:
@means "do notechothe command to the console". Command-echoing is controlled byecho onandecho off.Echois ON by default, so the command@echo offmeans "Turnechooff, but do notechothis line to the console.`Hence, once an
@echo offis executed, there is no need to put@before commands.In your third
echostatement, you have specified targAtname, which is undefined, hence the report shows nothing for that item.!in place of%means "the value of the variable as it is at run-time, not at parse-time" and is really only applicable where a statement invokes a loop which changes the variable, like aforloop, but asaschipflhas pointed out, it comes in useful to overcome the special-characters effects in anechostatement.Let's examine what batch does for one assignment:
Batch substitutes the
pathpart of the 1st parameter for%~p1so the actual command executed ishence it assigns
Atotargetpathand then attempts to executeB\hence the error message.On a string assignment, it is standard practice on SO to use the syntax
The quotes protect against stray trailing spaces on the command line, and will also cure most problems with special characters.
BTW:
will
echoall variables whose names starttarget