ConfigurationManager.AppSettings convert "\n" to "\\n" why?

Question

I have a AppSetting in web.config.

<add key="key" value="\n|\r"/>

When i read it by ConfigurationManager.AppSettings["key"] it gives "\\n|\\r". Why ?

Answer 1

In the debugger, becuase the backslash is a special character used for things like tabs (\t) and line endings (\n), it has to be escaped by the use of another backslash. Hence any text that contains an actual \ will be displayed as \. If you print it out to a file or use it in any other way, you will find your string only contains the one .

This isn't ConfigurationManager doing anything.

Answer 2

The backslash escaping syntax is only recognized inside of string literals by the C# compiler. Since your string is being read from an XML file at runtime, you need to use XML-compatible escaping (character entities) in order include those characters in your string. Thus, your app settings entry should look like the following:

<add key="key" value="&x10;|&x13;"/>

Because 10 and 13 are the hex values for linefeed and carriage return, respectively.

Like cjk said, the extra slash is being inserted by the debugger to indicate that it is seeing a literal slash and not an escape sequence.

Answer 3

I solved the same problem with a string replacement.
Not beautful.. but works!

ConfigurationManager.AppSettings["Key"].Replace("\\n", "\n")