CA2251: Use String.Equals over String.Compare

Property	Value
Rule ID	CA2251
Title	Use String.Equals over String.Compare
Category	Usage
Fix is breaking or non-breaking	Non-breaking
Enabled by default in .NET 9	No

Cause

The result of a call to String.Compare is compared to zero.

Rule description

String.Compare is designed to produce a total-order comparison that can be used for sorting. If you only care whether the strings are equal, it is both clearer and likely faster to use an equivalent overload of String.Equals.

How to fix violations

To fix violations of this rule, replace the expression comparing the result of String.Compare with a call to String.Equals.

When to suppress warnings

It is safe to suppress warnings from this rule.

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.

C#

#pragma warning disable CA2251
// The code that's violating the rule is on this line.
#pragma warning restore CA2251

To disable the rule for a file, folder, or project, set its severity to none in the configuration file.

ini

[*.{cs,vb}]
dotnet_diagnostic.CA2251.severity = none

For more information, see How to suppress code analysis warnings.

See also

• Performance warnings