MetaData Property Editor
The MetaData property editor allows you to add metadata to your product, this is passed over to the Payment Provider.
In the data type picker it is called UmbCheckout MetaData (in the eCommerce group). Use the alias umbCheckoutMetaData on your product. Editors add rows of Name and Value. It is stored as JSON; MetaData properties from UmbCheckout 1.x are moved to it when the site is upgraded.
The returned type is: Dictionary<string, string>

Programmatically add metadata
Section titled “Programmatically add metadata”You can programmatically add metadata by creating an IEnumerable<UmbCheckoutMetaData>() object
var metaData = new List<UmbCheckoutMetaData>{ new() { Name = "Dictionary Key 1", Value = "Dictionary Value 1" }, new() { Name = "Dictionary Key 2", Value = "Dictionary Value 2" }}