toJson method
Implementation
core.Map<core.String, core.dynamic> toJson() => {
if (chartId != null) 'chartId': chartId!,
if (contentUrl != null) 'contentUrl': contentUrl!,
if (sheetsChartProperties != null)
'sheetsChartProperties': sheetsChartProperties!,
if (spreadsheetId != null) 'spreadsheetId': spreadsheetId!,
};