如何将大于和小于添加到批处理文件变量中 [英] How can I add greater than and less than into a batch file variable

问题描述

当我尝试

@echo off
set PTag=^<BR^>
echo %PTag%

我什么也没得到.

现在有趣的是，如果在最后一次回声之后有一个空行，我会得到:

Now what's interesting is that if there's an empty line after the last echo, I get:

The syntax of the command is incorrect.

如果我删除了@echo，那么它实际上会输出

If I remove the @echo off, then it actually outputs

echo <BR>

我想在变量内添加各种HTML标记，然后将这些变量连接起来以创建将在文件中输出的HTML.

I want to add various HTML tags inside variables and then concatenate these variables to create an HTML that I will output in a file.

推荐答案

set PTag=^<BR^>将值<BR>设置为PTag

当您运行echo %PTag%时，它将展开为echo <BR>，这是无效的重定向.您需要使用此

When you run echo %PTag% it expands to echo <BR> which is an invalid redirection. You need to escape the < and > inside PTag by using this

set PTag=^^^<BR^^^>

第一个^会自行转义，然后下一个<或>

The first ^ escapes itself, then the next one escapes < or >

您也可以使用此

set "PTag=^<BR^>"

---

第二种原因:引号^失去其特殊含义

---

Reason for the second way: inside quotes ^ loses its special meaning

如果是引号(")，请切换引号标志；如果引号标志处于活动状态，则以下特殊字符不再特殊:^ & | < > ( ).

If it is a quote (") toggle the quote flag, if the quote flag is active, the following special characters are no longer special: ^ & | < > ( ).

^{Windows命令解释器(CMD.EXE)如何解析脚本?}

大多数特殊字符(^ & ( ) < > |以及标准定界符, ; = SPACE 一旦将它们放置在""之间，并且""本身不成为变量值的一部分， TAB )便失去其特殊含义.

most special characters (^ & ( ) < > | and also the standard delimiters , ; = SPACE TAB) lose their particular meaning as soon as ther are placed in between "", and the "" themselves do not become part of the variable value

^{批处理文件中的特殊字符}

---

现在，变量内部将具有值^<BR^>，它将把echo %PTag%扩展为

---

Now the variable will have the value ^<BR^> inside it, and it'll expand echo %PTag% to

echo ^<BR^>

这是有效的命令

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