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Design Warnings
CA1000: Do not declare static members on generic types
CA1001: Types that own disposable fields should be disposable
CA1002: Do not expose generic lists
CA1003: Use generic event handler instances
CA1004: Generic methods should provide type parameter
CA1005: Avoid excessive parameters on generic types
CA1006: Do not nest generic types in member signatures
CA1007: Use generics where appropriate
CA1008: Enums should have zero value
CA1009: Declare event handlers correctly
CA1010: Collections should implement generic interface
CA1011: Consider passing base types as parameters
CA1012: Abstract types should not have constructors
CA1013: Overload operator equals on overloading add and subtract
CA1014: Mark assemblies with CLSCompliantAttribute
CA1016: Mark assemblies with AssemblyVersionAttribute
CA1017: Mark assemblies with ComVisibleAttribute
CA1018: Mark attributes with AttributeUsageAttribute
CA1019: Define accessors for attribute arguments
CA1020: Avoid namespaces with few types
CA1021: Avoid out parameters
CA1023: Indexers should not be multidimensional
CA1024: Use properties where appropriate
CA1025: Replace repetitive arguments with params array
CA1026: Default parameters should not be used
CA1027: Mark enums with FlagsAttribute
CA1028: Enum storage should be Int32
CA1030: Use events where appropriate
CA1031: Do not catch general exception types
CA1032: Implement standard exception constructors
CA1033: Interface methods should be callable by child types
CA1034: Nested types should not be visible
CA1035: ICollection implementations have strongly typed members
CA1036: Override methods on comparable types
CA1038: Enumerators should be strongly typed
CA1039: Lists are strongly typed
CA1040: Avoid empty interfaces
CA1041: Provide ObsoleteAttribute message
CA1043: Use integral or string argument for indexers
CA1044: Properties should not be write only
CA1045: Do not pass types by reference
CA1046: Do not overload operator equals on reference types
CA1047: Do not declare protected members in sealed types
CA1048: Do not declare virtual members in sealed types
CA1049: Types that own native resources should be disposable
CA1050: Declare types in namespaces
CA1051: Do not declare visible instance fields
CA1052: Static holder types should be sealed
CA1053: Static holder types should not have constructors
CA1054: URI parameters should not be strings
CA1055: URI return values should not be strings
CA1056: URI properties should not be strings
CA1057: String URI overloads call System.Uri overloads
CA1058: Types should not extend certain base types
CA1059: Members should not expose certain concrete types
CA1060: Move P/Invokes to NativeMethods class
CA1061: Do not hide base class methods
CA1062: Validate arguments of public methods
CA1063: Implement IDisposable correctly
CA1064: Exceptions should be public
CA1065: Do not raise exceptions in unexpected locations
CA2210: Assemblies should have valid strong names
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CA1023: Indexers should not be multidimensional

Visual Studio 2010

TypeName

IndexersShouldNotBeMultidimensional

CheckId

CA1023

Category

Microsoft.Design

Breaking Change

Breaking

A public or protected type contains a public or protected indexer that uses more than one index.

Indexers, that is, indexed properties, should use a single index. Multi-dimensional indexers can significantly reduce the usability of the library. If the design requires multiple indexes, reconsider whether the type represents a logical data store. If not, use a method.

To fix a violation of this rule, change the design to use a lone integer or string index, or use a method instead of the indexer.

Suppress a warning from this rule only after carefully considering the need for the nonstandard indexer.

The following example shows a type, DayOfWeek03, with a multi-dimensional indexer that violates the rule. The indexer can be seen as a type of conversion and therefore is more appropriately exposed as a method. The type is redesigned in RedesignedDayOfWeek03 to satisfy the rule.

C#
C++
VB
Copy 

using System;

namespace DesignLibrary
{
    public class DayOfWeek03
    {
        string[,] dayOfWeek = {{"Wed", "Thu", "..."}, 
                               {"Sat", "Sun", "..."}};
                               // ...

        public string this[int month, int day]
        {
            get
            {
                return dayOfWeek[month - 1, day - 1];
            }
        }
    }

    public class RedesignedDayOfWeek03
    {
        string[] dayOfWeek = 
            {"Tue", "Wed", "Thu", "Fri", "Sat", "Sun", "Mon"};

        int[] daysInPreviousMonth = 
            {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30};

        public string GetDayOfWeek(int month, int day)
        {
            return dayOfWeek[(daysInPreviousMonth[month - 1] + day) % 7];
        }
    }
}
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