忽略R字符串中的转义字符（反斜杠）

While running an R-plugin in SPSS, I receive a Windows path string as input e.g.

在SPSS中运行R插件时，我收到一个Windows路径字符串作为输入，例如

'C:\Users\mhermans\somefile.csv'

I would like to use that path in subsequent R code, but then the slashes need to be replaced with forward slashes, otherwise R interprets it as escapes (eg. "\U used without hex digits" errors).

我想在后续的R代码中使用该路径，但是斜杠需要用正斜杠替换，否则R将其解释为转义（例如“\ UU，不使用十六进制数字”错误）。

I have however not been able to find a function that can replace the backslashes with foward slashes or double escape them. All those functions assume those characters are escaped.

然而，我无法找到一个可以用斜线替换反斜杠或双重逃避它们的函数。所有这些函数都假设这些字符被转义。

So, is there something along the lines of:

那么，是否有类似的东西：

>gsub('\\', '/', 'C:\Users\mhermans')
C:/Users/mhermans

3 个解决方案

#1

You can try to use the 'allowEscapes' argument in scan()

您可以尝试在scan（）中使用'allowEscapes'参数

X=scan(what="character",allowEscapes=F)
C:\Users\mhermans\somefile.csv

print(X)
[1] "C:\\Users\\mhermans\\somefile.csv"

#2

First you need to get it assigned to a name:

首先，您需要将其分配给名称：

pathname <- 'C:\\Users\\mhermans\\somefile.csv'

Notice that in order to get it into a name vector you needed to double them all, which gives a hint about how you could use regex:

请注意，为了将其添加到名称向量中，您需要将它们全部加倍，这提示了如何使用正则表达式：

 gsub("\\\\", "/", pathname)
# [1] "C:/Users/mhermans/somefile.csv"

You needed to doubly double the backslashes. The first of each couple of \'s is to signal to the grep machine that what nextcomes is a literal.

你需要加倍反斜杠。每一对中的第一个是向grep机器发出信号，表明接下来的是文字。

#3

If file E:\Data\junk.txt contains the following text (without quotes): C:\Users\mhermans\somefile.csv

如果文件E：\ Data \ junk.txt包含以下文本（不带引号）：C：\ Users \ mhermans \ somefile.csv

You may get a warning with the following statement, but it will work:

您可能会收到以下声明的警告，但它会起作用：

 texinp <- readLines("E:\\Data\\junk.txt")

If file E:\Data\junk.txt contains the following text (with quotes): "C:\Users\mhermans\somefile.csv"

如果文件E：\ Data \ junk.txt包含以下文本（带引号）：“C：\ Users \ mhermans \ somefile.csv”

The above readlines statement might also give you a warning, but will now contain:

上面的readlines语句也可能会给你一个警告，但现在包含：

"\"C:\Users\mhermans\somefile.csv\""

“\” C：\用户\ mhermans \ somefile.csv \ “”

So, to get what you want, make sure there aren't quotes in the incoming file, and use:

因此，要获得所需内容，请确保传入文件中没有引号，并使用：

 texinp <- suppressWarnings(readLines("E:\\Data\\junk.txt"))

#1