CA1311: Specify a culture or use an invariant version
| Property | Value |
|---|---|
| Rule ID | CA1311 |
| Title | Specify a culture or use an invariant version |
| Category | Globalization |
| Fix is breaking or non-breaking | Non-breaking |
| Enabled by default in .NET 9 | No |
Cause
A call is made to String.ToUpper() or String.ToLower() without specifying a culture.
Rule description
Specify a culture or use an invariant culture to avoid implicit dependency on the current culture when calling ToUpper or ToLower. Using an invariant culture yields consistent results regardless of the culture of an application.
How to fix violations
Instead of calling the parameterless String.ToUpper() or String.ToLower() methods, call ToUpper(CultureInfo) or ToUpperInvariant(), or ToLower(CultureInfo) or ToLowerInvariant().
Example
The following code snippet shows a violation of rule CA1311:
string s = "hello";
s = s.ToLower();
Dim s As String = "hello"
s.ToLower()
The following code snippet fixes the violation:
string s = "hello";
s = s.ToLowerInvariant();
Dim s As String = "hello"
s.ToLowerInvariant()
When to suppress warnings
It's safe to suppress a warning from this rule if you're certain that Thread.CurrentCulture will never change.
Suppress a warning
If you just want to suppress a single violation, add preprocessor directives to your source file to disable and then re-enable the rule.
#pragma warning disable CA1311
// The code that's violating the rule is on this line.
#pragma warning restore CA1311
To disable the rule for a file, folder, or project, set its severity to none in the configuration file.
[*.{cs,vb}]
dotnet_diagnostic.CA1311.severity = none
For more information, see How to suppress code analysis warnings.
