Batch file 条目列表中的子字符串

我有一个包含文件名列表的变量，根据扩展名，我需要执行不同的操作。 我无法提取循环内的扩展

set BINARIES=file1.dll fil2.dll fil3.sys

:: for each file in list of binaries do
FOR %%G IN (%BINARIES%) DO (
    :: if extension is dll
    if /i [%%G:~-4%]==[.dll] (
        echo dll file
        ) else (
            echo sys file
        )
)

---

如果条件总是失败。如何正确提取扩展名。

我不知道您是否可以使用此扩展名：%%G:~-4%

此外，还必须使用变量的延迟展开。 关键是使用“！”而不是在某些地方使用“%”。 使用“set/？”进行检查，它给出了一个（令人困惑的）示例

我不太记得它背后的理论，但这对我很有用：

setlocal enabledelayedexpansion

set BINARIES=file1.dll fil2.dll fil3.sys

:: for each file in list of binaries do
FOR %%G IN (%BINARIES%) DO (
    :: if extension is dll
    set x=%%g
    set y=!x:~-4!
    if /i [%y%]==[.dll] (
        echo dll file
        ) else (
            echo sys file
        )
)

从cmd shell窗口的帮助

获取/？

：

In addition, substitution of FOR variable references has been enhanced. You can now use the following optional syntax: %~I - expands %I removing any surrounding quotes (") %~fI - expands %I to a fully qualified path name %~dI - expands %I to a drive letter only %~pI - expands %I to a path only %~nI - expands %I to a file name only %~xI - expands %I to a file extension only %~sI - expanded path contains short names only %~aI - expands %I to file attributes of file %~tI - expands %I to date/time of file %~zI - expands %I to size of file %~$PATH:I - searches the directories listed in the PATH environment variable and expands %I to the fully qualified name of the first one found. If the environment variable name is not defined or the file is not found by the search, then this modifier expands to the empty string The modifiers can be combined to get compound results: %~dpI - expands %I to a drive letter and path only %~nxI - expands %I to a file name and extension only %~fsI - expands %I to a full path name with short names only %~dp$PATH:I - searches the directories listed in the PATH environment variable for %I and expands to the drive letter and path of the first one found. %~ftzaI - expands %I to a DIR like output line 此外，还增强了变量引用的替换。 现在可以使用以下可选语法： %~I-展开%I以删除任何周围的引号（“） %~fI-将%I扩展为完全限定的路径名 %~dI-仅将%I扩展为驱动器号 %~pI-仅将%I扩展到路径 %~nI-仅将%I扩展为文件名 %~xI-仅将%I扩展为文件扩展名 %~sI-扩展路径仅包含短名称 %~aI-将%I扩展为文件的文件属性 %~tI-将%I扩展到文件的日期/时间 %~zI-将%I扩展到文件大小 %~$PATH:I-搜索路径中列出的目录 环境变量并将%I展开为 找到的第一个的完全限定名。 如果环境变量名不是 已定义或找不到该文件 搜索，然后此修改器扩展到 空字符串 可以组合修改器以获得复合结果： %~dpI-仅将%I扩展为驱动器号和路径 %~nxI-仅将%I扩展为文件名和扩展名 %~fsI-将%I扩展为仅包含短名称的完整路径名 %~dp$PATH:I-搜索路径中列出的目录 %I的环境变量，并扩展到 找到的第一个驱动器号和路径。 %~ftzaI-将%I扩展为类似DIR的输出行 In addition, substitution of FOR variable references has been enhanced. You can now use the following optional syntax: %~I - expands %I removing any surrounding quotes (") %~fI - expands %I to a fully qualified path name %~dI - expands %I to a drive letter only %~pI - expands %I to a path only %~nI - expands %I to a file name only %~xI - expands %I to a file extension only %~sI - expanded path contains short names only %~aI - expands %I to file attributes of file %~tI - expands %I to date/time of file %~zI - expands %I to size of file %~$PATH:I - searches the directories listed in the PATH environment variable and expands %I to the fully qualified name of the first one found. If the environment variable name is not defined or the file is not found by the search, then this modifier expands to the empty string The modifiers can be combined to get compound results: %~dpI - expands %I to a drive letter and path only %~nxI - expands %I to a file name and extension only %~fsI - expands %I to a full path name with short names only %~dp$PATH:I - searches the directories listed in the PATH environment variable for %I and expands to the drive letter and path of the first one found. %~ftzaI - expands %I to a DIR like output line

set BINARIES=file1.dll fil2.dll fil3.sys

FOR %%G IN (%BINARIES%) DO echo %%G has a %%~xG extension.