CA1307: Specify StringComparison

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TypeName SpecifyStringComparison
CheckId CA1307
Category Microsoft.Globalization
Breaking Change Non-breaking

Cause

A string comparison operation uses a method overload that does not set a StringComparison parameter.

Rule Description

Many string operations, most important the Compare and Equals methods, provide an overload that accepts a StringComparison enumeration value as a parameter.

Whenever an overload exists that takes a StringComparison parameter, it should be used instead of an overload that does not take this parameter. By explicitly setting this parameter, your code is often made clearer and easier to maintain.

How to Fix Violations

To fix a violation of this rule, change string comparison methods to overloads that accept the StringComparison enumeration as a parameter. For example: change String.Compare(str1, str2) to String.Compare(str1, str2, StringComparison.Ordinal).

When to Suppress Warnings

It is safe to suppress a warning from this rule when the library or application is intended for a limited local audience and will therefore not be localized.

See Also

Globalization Warnings CA1309: Use ordinal StringComparison