用法一
Type TProc=procedure() of object;
procedure Callback(proc:TProc);
begin
...
end;
procedure myproc()
begin
...
end;
Callback(myproc);
用法二
type TProc= reference to Procedure();
procedure Callback(proc:TProc);
begin
....
end;
Callback(
procedure()begin
end;
);
原文：https://www.cnblogs.com/onexyz/p/12090649.html