Hi SungGon Park,
Requirement: How to serialize Content and ContentTemplate of the node from stencil dragging
In SfDiagram, you cannot serialize the Content and ContentTemplate of every diagramming object. If you want to preserve the ContentTemplate of diagramming objects, keep them in resources and apply them once the diagramming objects are added to the Diagram page.
We have modified the provided sample and attached its modified version for your reference. In that sample, we added a custom class for NodeViewModel and a custom property to store the Content key value. Once a node is added to the diagram from the stencil, the content is added to the node using that ContentKey property.
Regards,
Deepa Thiruppathy
Attachment:
SyncfusionStencilTest_modified_7cf315e1.zip