[D365] Add display method via Extension
Adding a display method to a standard table in D365 can be confusing because most parts of the documentation state it should be implemented as static method with the table as only parameter and writte in the control's Data Method
like this: MyClass::staticDisplayMethod
.
This does not only look ugly but there is a better way!
First, create an Extension class for the standard table you want to add the display method to:

Then implement your display method as instance method:
[ExtensionOf(tableStr(TmpPurchLine))]
public final class TmpPurchLine_Extension
{
public display AmountCur myQtyField()
{
return this.PurchQty;
}
}

Then create a form extension for the standard form you want to add your display method to:

Add a new control of the correct type to your design (example: Real control) and then set the property Data Source
to the standard table you created your extension for and the Data Method
property to the name of your extension class and display method connected by a dot. Example: TmpPurchLine_Extension.myQtyField

This does look strange at first but works and you can avoid implementing static methods.