Why is this an issue?
Non-encoded control characters and whitespace characters are often injected in the
source code because of a bad manipulation. They are either invisible or difficult to recognize, which can result in bugs when the string is not what
the developer expects. If you actually need to use a control character use their encoded version:
- ASCII, for example
\n and \t
- Unicode, for example
U+000D and U+0009
This rule raises an issue when the following characters are seen in a string literal:
Exceptions
How to fix it
Code examples
Noncompliant code example
string tabInside = "A B"; // Noncompliant: contains a tabulation
string zeroWidthSpaceInside = "foobar"; // Noncompliant: contains a U+200B character inside
Console.WriteLine(zeroWidthSpaceInside); // Prints "foo?bar"
Compliant solution
string tabInside = "A\tB"; // Compliant: escaped value
string zeroWidthSpaceInside = "foo\u200Bbar"; // Compliant: escaped value
Console.WriteLine(zeroWidthSpaceInside); // Prints "foo?bar"
Resources
Documentation
