jsonmapper.pas

// Copyright (c) 2017, Jordi Corbilla
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// - Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// - Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// - Neither the name of this library nor the names of its contributors may be
// used to endorse or promote products derived from this software without
// specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.

procedure TJsonMapper.Map(const refObject: TObject; const refJson: TJSONObject);
var
  propertyIndex: Integer;
  propertyCount: Integer;
  propertyList: PPropList;
  propertyInfo: PPropInfo;
  value : string;
  valueInt : integer;

  function GetPropertyName(value: string): string;
  var
    lowerText : string;
    restText : string;
  begin
    if length(value) > 0 then
    begin
      lowerText := AnsiLeftStr(value, 1);
      lowerText := AnsiLowerCase(lowerText);
      restText := AnsiRightStr(value, length(value)-1);
      result := lowerText + restText;
    end
    else
      result := value;
  end;

const
  TypeKinds: TTypeKinds = [tkString, tkInteger];
begin
  propertyCount := GetPropList(refObject.ClassInfo, TypeKinds, nil);
  GetMem(propertyList, propertyCount * SizeOf(PPropInfo));
  try
    GetPropList(refObject.ClassInfo, TypeKinds, propertyList);
    for propertyIndex := 0 to propertyCount - 1 do
    begin
      propertyInfo := propertyList^[propertyIndex];
      if Assigned(propertyInfo^.SetProc) then
      begin
        value := GetPropertyName(propertyInfo.Name);
        if (refJson.Get(value) <> nil) then
        begin
          case propertyInfo^.PropType^.Kind of
            tkString:
              begin
                  value := (refJson.Get(value).JsonValue as TJSONString).Value;
                  SetStrProp(refObject, propertyInfo, value);
              end;
            tkInteger:
            begin
                valueInt := (refJson.Get(value).JsonValue as TJSONNumber).AsInt;
                SetOrdProp(refObject, propertyInfo, valueInt);
            end;
          end;
        end;
      end;
    end;
  finally
    FreeMem(propertyList);
  end;
end;