SP.WebParts.WebPartDefinition.id property (sp.js)
Gets a value that specifies the Web Part identifier of the Web Part.
Applies to: apps for SharePoint | SharePoint Foundation 2013 | SharePoint Server 2013
var value =SP.WebParts.WebPartDefinition.get_id()
Return value
Returns a SP.Guid instance representing the Web Part identifier of the Web Part.
Remarks
This value must be unique for each Web Part.