Read one attachment. A text file comes back as its text; a binary file is described, not decoded. An attached message comes back with expand set to microsoft.graph.itemattachment/item.
Use the selectqueryparametertoreturnasubsetofpropertiesforaresource.Withselect, you can specify a subset or a superset of the default properties. For example, from,subject returns only the from and subject properties.
$expand
string
Use $expand to get the properties of an item attachment (contact, event, or message), for example microsoft.graph.itemattachment/item.