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--- indexers_indexed_property [2018/09/06 19:25] – created wolfgangriedmann
+++ indexers_indexed_property [2018/09/11 08:37] (current) – wolfgangriedmann
@@ Line 1: / Line 1: @@
 ====== Indexers and indexed properties ======
+Indexers are a new concept for xBase developers. They permit to access the properties of an object like an array. Please see this sample class:
+<code visualfoxpro>class IndexerTest
+protect oValues	as List<string>
+constructor()
+oValues := List<string>{}
+return
+property self[ nIndex as int ] as string
+  get
+    if oValues:Count >= nIndex
+      return oValues[nIndex-1]
+    else
+      return ""
+    endif
+  end get
+  set
+    while oValues:Count < nIndex
+      oValues:Add( "" )
+    end
+    oValues[nIndex-1]		:= value
+  end set
+end property
+end class</code>
+This class can be used like this:
+<code visualfoxpro>function Start( ) as void
+local oTest as IndexerTest
+local nI as int
+oTest := IndexerTest{}
+oTest[1] := "Chris"
+oTest[2] := "Fabrice"
+oTest[3] := "Nikos"
+oTest[4]:= "Robert"
+for nI := 1 upto 5
+  Console.WriteLine( i"Element {nI}:" + oTest[nI] )
+next
+return</code>
+Classes with indexed properties can also be used like classes with dynamic arrays. Please see this sample:
+<code visualfoxpro>class IndexedProperty
+protect _oValues as Dictionary<string,string>
+constructor()
+  _oValues		:= Dictionary<string,string>{}
+return
+property self[cName as string] as string
+  get
+    local cValue as string
+    if _oValues:TryGetValue( cName, OUT cValue ) == false
+      cValue := "< not assigned >"
+    endif
+    return cValue
+  end get
+  set
+    if _oValues:ContainsKey( cName )
+      _oValues[cName]		:= value
+    else
+      _oValues:Add( cName, value )
+    endif
+end set
+end property
+end class</code>
+To be used like this:
+<code visualfoxpro>oObject := IndexedProperty{}
+oObject["MyProp"] := "Hello X#"
+oObject["Prop2"] := "Hello again"
+System.Console.WriteLine( "MyProp:" + oObject["MyProp"] )
+System.Console.WriteLine( "Prop2:" + oObject["Prop2"] )
+System.Console.WriteLine( "Prop3:" + oObject["Prop3"] )</code>
+Please see also this Microsoft article: [[https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/indexers/|https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/indexers/]]
+And there is also a forum thread about this:
 Please see https://www.xsharp.info/forum/public-product/839-indexer-syntax