Using Caché Objects - InterSystems Documentation

Executing Methods
10.1.3 Executing Class Methods
You can execute a class method without having an object instance. You can also execute a
class method from a method of the same class. In this case, you can invoke the method as
you would an instance method.
To execute a class method, use the following syntax:
Do ##class(Classname).MethodName(arglist)
Set value = ##class(Classname).MethodName(arglist)
where classname is the name of the class with the relevant method,MethodName is the name
of the method to execute, and arglist is the list of arguments passed to the method. value, in
the second line of code, is a local variable that receives the return value of the method. The
class name may contain a package name; if omitted, the class compiler determines the correct
package name to use (this name resolution is explained in the Packages chapter).
For example, you can execute the PurgeAll method of the ReportCard class:
Do ##class(ReportCard).PurgeAll()
Or you can use a fully-qualified class name:
Do ##class(MyApp.ReportCard).PurgeAll()
Similarly, you can execute the Exists method of the %File class (which determines if a file
exists) using the following code:
Set exists = ##class(%File).Exists("\temp\file.txt")
where exists is a true (1) or false (0) value.
10.1.4 Executing Methods Using In-Memory Instances
If an instance of the class is in memory, you can execute a class or instance method using the
syntax that appears in either of the following lines of code:
Do oref.MethodName(arglist)
Set value = oref.MethodName(arglist)
where oref is the OREF of the relevant object, MethodName is the name of the method to
execute, and arglist is the list of arguments passed to the method. value, in the second line
of code, is a local variable that receives the return value of the method.
For example, you can also execute the PurgeAll instance method of the ReportCard class
using this syntax:
Using Caché Objects 69