C# getting the path of %AppData%

Question

C# 2008 SP1

I am using the code below:

dt.ReadXml(\"%AppData%\\\\DateLinks.xml\");

However, I am getting an exception that points t

Answer 1

I don't think putting %AppData% in a string like that will work.

try

Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData).ToString()

Answer 2

To get the AppData directory, it's best to use the GetFolderPath method:

Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData)

(must add using System if not present).

%AppData% is an environment variable, and they are not automatically expanded anywhere in .NET, although you can explicitly use the Environment.ExpandEnvironmentVariable method to do so. I would still strongly suggest that you use GetFolderPath however, because as Johannes Rössel points out in the comment, %AppData% may not be set in certain circumstances.

Finally, to create the path as shown in your example:

var fileName = Path.Combine(Environment.GetFolderPath(
    Environment.SpecialFolder.ApplicationData), "DateLinks.xml");

Answer 3

You can also use

Environment.ExpandEnvironmentVariables("%AppData%\\DateLinks.xml");

to expand the %AppData% variable.

Answer 4

AppData ⇝ Local aka (C:\Users\<user>\AppData\Local):

Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData)

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AppData ⇝ Roaming aka (C:\Users\<user>\AppData\Roaming):

Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData)

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Additionally, it could be handy to know:

• Environment.SpecialFolder.ProgramFiles - for Program files X64 folder
• Environment.SpecialFolder.ProgramFilesX86 - for Program files X86 folder

For the full list check here.