Fix misleading equality testing method documentation in C# objects guide #47672
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Co-authored-by: BillWagner <[email protected]>
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This PR addresses misleading information about equality testing methods in the C# objects documentation that could confuse developers about when to use different equality comparison methods.
Issues Fixed
1. Incorrect recommendation for identity comparison
The documentation incorrectly suggested using
Object.Equalsto determine if two class instances refer to the same location in memory (identity comparison). However,Object.Equalscan be overridden and doesn't guarantee reference equality. The correct method for identity comparison isObject.ReferenceEquals.2. Misleading guarantees about ValueType.Equals behavior
The documentation stated that
ValueType.Equalsdetermines whether instance fields have the same values, but this is misleading becauseValueType.Equalscan be overridden. The text now clarifies this is the default behavior.Changes Made
System.Object.EqualstoSystem.Object.ReferenceEqualsfor identity comparisonValueType.Equals"by default" determines field equality, rather than guaranteeing this behaviorValueTypeimplementation detailsThese changes maintain the beginner-friendly tone while providing technically accurate information, as requested by @BillWagner in the issue comments.
Validation
Fixes #29582.
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