Instead of relying on Delphi’s internal object layout you could also have your objects implement another interface which would simply return the object. This, of course, only works if you have access to the source code of the objects to begin with, but you probably shouldn’t even use these hacks if you don’t have access … Read more
This is easier as thought (thanks to Hallvard’s Blog – Hack#14: Changing the class of an object at run-time): procedure PatchInstanceClass(Instance: TObject; NewClass: TClass); type PClass = ^TClass; begin if Assigned(Instance) and Assigned(NewClass) and NewClass.InheritsFrom(Instance.ClassType) and (NewClass.InstanceSize = Instance.InstanceSize) then begin PClass(Instance)^ := NewClass; end; end; type TMyButton = class(TButton) public procedure Click; override; end; … Read more
You may have more luck skipping the COM part by using my project template for unmanaged exports class MyDllClass { [DllExport] static int MyDllMethod(int i) { MessageBox.Show(“The number is ” + i.ToString()); return i + 2; } } In Delphi, you’d import it like so: function MyDllMethod(i : Integer) : Integer; stdcall; extern ‘YourAssembly.dll’; I … Read more
For some background information have a look here: http://www.siao2.com/2010/03/19/9980203.aspx So it seems this problem manifests itself on Vista as well as Windows 7. It occurs because Microsoft seems to be in the process of deprecating the Locale ID in favor of the Locale Name. To summarize: The relevant API calls all operate on registry values … Read more
You must use the SHGetImageList function, to get the image list with the larger icons. Here you have an example in delphi uses ShellApi, Commctrl, ShlObj; const SHIL_LARGE = $00; //The image size is normally 32×32 pixels. However, if the Use large icons option is selected from the Effects section of the Appearance tab in … Read more
This problem can be solved like so: Obtain or implement a threadsafe version of AllocateHwnd and DeallocateHwnd. Replace the VCL’s unsafe versions of these functions. For item 1 I use Primož Gabrijelcic’s code, as described on his blog article on the subject. For item 2 I simply use the very well-known trick of patching the … Read more
You have to check for Terminate in the thread for this to work. For instance: procedure TMyThread.Execute; begin while not Terminated do begin //Here you do a chunk of your work. //It’s important to have chunks small enough so that “while not Terminated” //gets checked often enough. end; //Here you finalize everything before thread terminates … Read more
If you use sl.Free, the object is freed but the variable sl still points to the now invalid memory. Use FreeAndNil(sl) to both free the object and clear the pointer. By the way, if you do: var sl1, sl2: TStringList; begin sl1 := TStringList.Create; sl2 := sl1; FreeAndNil(sl1); // sl2 is still assigned and must … Read more
TurboPower LockBox 3.1.0 is now released. It supports: Delphi 2007 and Delphi 2010 Unicodestrings for Delphi 2010 AES, DES, 3DES, Blowfish and Twofish ciphers A long list of block chaining modes MD5 and SHA1 hashes RSA encryption, decryption, signature and verification Variable length RSA keys – Almost no contraints on the range. D-Unit test code … Read more
TurboPower LockBox 3.1.0 is now released. It supports: Delphi 2007 and Delphi 2010 Unicodestrings for Delphi 2010 AES, DES, 3DES, Blowfish and Twofish ciphers A long list of block chaining modes MD5 and SHA1 hashes RSA encryption, decryption, signature and verification Variable length RSA keys – Almost no contraints on the range. D-Unit test code … Read more