Change how TCSSBuilder generates CSS

The order the selectors were generated by TCSSBuilder.AsString was
indeterminate (it was the order a dictionary enumerated them). This was
changed so the the selectors are now rendered in the order they were
created.

This was done for cases where the ordering of the CSS selectors matters.

Author: delphidabbler

Src/UCSSBuilder.pas

@@ -77,7 +77,8 @@   TCSSBuilder = class(TObject)
       // Class that maps CSS selector names to selector objects
       TCSSSelectorMap = TObjectDictionary<string,TCSSSelector>;
     var
-      fSelectors: TCSSSelectorMap;  // Maps selector names to selector objects
+      fSelectors: TCSSSelectorMap;    // Maps selector names to selector objects
+      fSelectorNames: TList<string>;  // Lists selector names in order created
     function GetSelector(const Selector: string): TCSSSelector;
       {Read access method for Selectors property. Returns selector object with
       given name.
@@ -105,10 +106,13 @@   TCSSBuilder = class(TObject)
     procedure Clear;
       {Clears all selectors from style sheet and frees selector objects.
       }
+
+    ///  <summary>Generates CSS code representing the style sheet.</summary>
+    ///  <returns><c>string</c>. The required CSS.</returns>
+    ///  <remarks>The selectors are returned in the order they were created.
+    ///  </remarks>
     function AsString: string;
-      {Generates CSS code representing the style sheet.
-        @return Required CSS code.
-      }
+
     property Selectors[const Selector: string]: TCSSSelector
       read GetSelector;
       {Array of CSS selectors in style sheet, indexed by selector name}
@@ -189,26 +193,29 @@ function TCSSBuilder.AddSelector(const Selector: string): TCSSSelector;
 begin
   Result := TCSSSelector.Create(Selector);
   fSelectors.Add(Selector, Result);
+  fSelectorNames.Add(Selector);
 end;
 
 function TCSSBuilder.AsString: string;
-  {Generates CSS code representing the style sheet.
-    @return Required CSS code.
-  }
 var
+  SelectorName: string;   // name of each selector
   Selector: TCSSSelector; // reference to each selector in map
 begin
   Result := '';
-  for Selector in fSelectors.Values do
+  for SelectorName in fSelectorNames do
+  begin
+    Selector := fSelectors[SelectorName];
     if not Selector.IsEmpty then
       Result := Result + Selector.AsString;
+  end;
 end;
 
 procedure TCSSBuilder.Clear;
   {Clears all selectors from style sheet and frees selector objects.
   }
 begin
-  fSelectors.Clear; // frees selector objects in .Values[]
+  fSelectorNames.Clear;
+  fSelectors.Clear;       // frees owened selector objects in dictionary
 end;
 
 constructor TCSSBuilder.Create;
@@ -221,13 +228,15 @@ constructor TCSSBuilder.Create;
   fSelectors := TCSSSelectorMap.Create(
     [doOwnsValues], TTextEqualityComparer.Create
   );
+  fSelectorNames := TList<string>.Create;
 end;
 
 destructor TCSSBuilder.Destroy;
   {Destructor. Tears down object.
   }
 begin
-  fSelectors.Free;    // frees selector objects in fSelectors.Values[]
+  fSelectorNames.Free;
+  fSelectors.Free;    // frees owened selector objects in dictionary
   inherited;
 end;