Map Class

Definition

public ref class Map : Microsoft::Dynamics::Ax::Xpp::XppObjectBase

public class Map : Microsoft.Dynamics.Ax.Xpp.XppObjectBase

type Map = class
    inherit XppObjectBase

Public Class Map
Inherits XppObjectBase

Inheritance

Microsoft.Dynamics.AX.KernelInterop.ProxyBase

XppObjectBase

Map

Remarks

Both the key and the value can be any valid X++ type, including objects. The types of the key and the value are specified in the declaration of the map. The way in which maps are implemented means that access to the values is very fast. Multiple keys can map to the same value, but one key can map to only one value at a time. If you add a (key, value) pair that has an existing key value, it replaces the existing pair with that key value. The (key, value) pairs in a map can be traversed by using the MapEnumerator class.

The following example illustrates how to invert a map. A map can be inverted only if no value is mapped to by two different keys. The number of elements in the Map.keySet method and the Map.valueSet method is compared to check this. Otherwise, the elements are traversed in the incoming map and inserted into the result map. The function that performs the inversion, the invertMap method, works regardless of the types of the keys and values.

{ 
    Map example; 
    Map invertMap(map _mapToInvert) 
    { 
        MapEnumerator en; 
        Map result =  new Map( 
            _mapToInvert.valueType(), 
            _mapToInvert.keyType()); 
        if (_mapToInvert.keySet().elements()  
            != _mapToInvert.valueSet().elements()) 
        { 
            return null; 
        } 
        en = new MapEnumerator(_mapToInvert); 
        while (en.moveNext()) 
        { 
            result.insert(en.currentValue(), en.currentKey()); 
        } 
        return result; 
    } 
    ; 
    // Fill in a few values. 
    example = new Map(Types::Integer, Types::String); 
    example.insert (1, "one"); 
    example.insert (2, "two"); 
    print invertMap(example).toString(); 
    pause; 
    // Now two keys (2 and 3) map to the same value 
    // so can't create inverse map 
    example.insert (3, "two"); 
    if (!invertMap(example)) 
    { 
        print "Could not create the map"; 
    } 
    pause; 
}

Constructors

Fields

Properties

Methods

Applies to