- Add McJson.pas into project
  - Add mcjson into uses clause
  - Add variable and assign it as TMcJsonItem (ie: var  js : tmcjsonitem; )
  - Create the variable (ie: var := TMcJsonItem.create(); )
  - free the variable when not in use

<code>
var
  Form1: TForm1;
  js : TMcJsonItem;
  
procedure TForm1.FormShow(Sender: TObject);
begin
   js := TMcJsonItem.create();
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
   js.Free;
end;
</code>

Add into json variable
<code>
   Js.Add('key1').AsInteger := 1;
   Js.Add('key2').AsBoolean := True;
   Js.Add('key3').AsNumber  := 1.234;
   Js.Add('key4').AsString  := 'value 1';
   // add an array
   Json.Add('array', jitArray);
   for i := 1 to 3 do Js['array'].Add.AsInteger := i;
</code>
  
Check if a key exist
<code>
   if js.HasKey('key1') then MessageDlg('Key found');
</code>

To update value of key
<code>
   if js.HasKey(key) then begin
      js.Delete(key);
      js.Add(key).AsString := value;
   end;
</code>   

To get value of key
<code>
   ShowMessage(js.Values[key].AsString);
</code>

Parsing line break solution
<code>
   js.add(key).asstring := stringreplace(value,slinkbreak,' ',[rfreplaceall]);
</code>

Check if a string is a valid json
<code>
   try
      js.asjson := '{"i": 123, "f": 123.456, "s": "abc", "b": true, "n": null}';
   except
      showmessage('not valid json');
   end;
</code>

Display the whole json string
<code>
   showmessage(js.asjson);
</code>

More info at https://github.com/hydrobyte/McJSON