Unrecognized escape sequence for path string containing backslashes

Question

The following code generates a compiler error about an "unrecognized escape sequence" for each backslash:

string foo = "D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";

I guess I need to escape backslash? How do I do that?

Sommerville

Answer 1

You can either use a double backslash each time

string foo = "D:\\Projects\\Some\\Kind\\Of\\Pathproblem\\wuhoo.xml";

or use the @ symbol

string foo = @"D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";

Hydroxy

This also helped to resolve an Html.TextBoxFor issue that I was having. Using the @ before the regular expression resolved the Unrecognized escape sequence, where the double backslash failed. – Men

Answer 2

Try this:

string foo = @"D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";

The problem is that in a string, a \ is an escape character. By using the @ sign you tell the compiler to ignore the escape characters.

You can also get by with escaping the \:

string foo = "D:\\Projects\\Some\\Kind\\Of\\Pathproblem\\wuhoo.xml";

Hokku

FWIW and to help Googlebot, the term for @"" is a "verbatim string literal". Though I've also heard it referred to as just "string literal", that technically includes the "regular string literal" of just "". msdn.microsoft.com/en-us/library/aa691090(VS.71).aspx – Imprimatur

Answer 3

var foo = @"D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";

Unroll

On a minor note, a " is then escaped like "" – Passer

Answer 4

If your string is a file path, as in your example, you can also use Unix style file paths:

string foo = "D:/Projects/Some/Kind/Of/Pathproblem/wuhoo.xml";

But the other answers have the more general solutions to string escaping in C#.

Veii

Answer 5

string foo = "D:\\Projects\\Some\\Kind\\Of\\Pathproblem\\wuhoo.xml";

This will work, or the previous examples will, too. @"..." means treat everything between the quote marks literally, so you can do

@"Hello
world"

To include a literal newline. I'm more old school and prefer to escape "\" with "\\"

Cyanohydrin

But double " are not treated literally. – Smutchy