$re = '/((object|inherited) \w+:[ ](TMgDBEdit).*?)((Color = clInactiveCaptionText\n)|(\n\s+end))/mis';
$str = '        object Ed_PRO_ST_DESCRICAO: TMgDBEdit
          Left = 132
          Top = 81
          Width = 675
          Height = 21
          AutoSize = False
          Color = clInactiveCaptionText
          DataField = \'PRO_ST_DESCRICAO\'
          DataSource = Dm_AdmInt.Ds_Produtos_
          TabOrder = 4
          OnChange = Ed_PRO_ST_DESCRICAOChange
          OnExit = Ed_PRO_ST_DESCRICAOExit
          OnKeyPress = Ed_PRO_ST_DESCRICAOKeyPress
          Password = False
        end
        object Ed_PRO_ST_NARRATIVA1: TMgDBMemo
          Left = 132
          Top = 157
          Width = 675
          Height = 78
          DataField = \'PRO_ST_NARRATIVA\'
          DataSource = Dm_AdmInt.Ds_Produtos_
          MaxLength = 500
          ScrollBars = ssVertical
          TabOrder = 7
        end
';
$subst = "\1ParentFont = True\n";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php