我真的很困惑。
// initial class
type
TTestClass =
class( TInterfacedObject)
end;
{...}
// test procedure
procedure testMF();
var c1, c2 : TTestClass;
begin
c1 := TTestClass.Create(); // create, addref
c2 := c1; // addref
c1 := nil; // refcount - 1
MessageBox( 0, pchar( inttostr( c2.refcount)), '', 0); // just to see the value
end;
它应该显示 1,但它显示 0。无论我们将执行多少次分配,值都不会改变!为什么不?
最佳答案
仅当您分配给接口(interface)变量而不是对象变量时,才会修改 Refcount。
procedure testMF();
var c1, c2 : TTestClass;
Intf1, Intf2 : IUnknown;
begin
c1 := TTestClass.Create(); // create, does NOT addref
c2 := c1; // does NOT addref
Intf1 := C2; //Here it does addref
Intf2 := C1; //Here, it does AddRef again
c1 := nil; // Does NOT refcount - 1
Intf2 := nil; //Does refcount -1
MessageBox( 0, pchar( inttostr( c2.refcount)), '', 0); // just to see the value
//Now it DOES show Refcount = 1
end;
关于delphi - 为什么我的 Delphi 对象没有调用 _AddRef 和 _Release?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/3920470/