Compiler Error CS1009
Unrecognized escape sequence
An unexpected character follows a backslash (\) in a string. The compiler expects one of the valid escape characters. For more information, see Character Escapes.
The following sample generates CS1009.
// CS1009-a.cs
class MyClass
{
static void Main()
{
// The following line causes CS1009.
string a = "\m";
// Try the following line instead.
// string a = "\t";
}
}
A common cause of this error is using the backslash character in a file name, as the following example shows.
string filename = "c:\myFolder\myFile.txt";
To resolve this error, use "\\" or the @-quoted string literal, as the following example shows.
// CS1009-b.cs
class MyClass
{
static void Main()
{
// The following line causes CS1009.
string filename = "c:\myFolder\myFile.txt";
// Try one of the following lines instead.
// string filename = "c:\\myFolder\\myFile.txt";
// string filename = @"c:\myFolder\myFile.txt";
}
}