EurekaLog-v7.10.1.0,for delphi xe

This sample uses 2 DLLs - which illustrate usage of simple functions and forms in DLLs with EurekaLog. Both DLLs are compiled with "Standalone DLL" application type, which means EurekaLog code will be injected in each DLL. Therefore, such DLL are autonomous and can be used in both EurekaLog-enabled host and non EurekaLog-enabled host. DLL with forms is the same "Standalone DLL", but with additional "Forms" hook installed: see Advanced/Code/Hooks for various options. Note: "Standalone DLL" with "VCL Forms" hook is essentially the same as "VCL Forms Application". An important consideration when creating standalone DLL: never let exception leave your DLL. Always place try/except block around each exported functions and any other published code (such as callback functions). Note: try/except block may be implicit - for example, you can use compiler's magic provided for the safecall keyword. You should handle each exception within DLL and report "failure" state to the caller (the host). There are many different ways to do this. This sample illustrates 3 common approaches: 1. Simple Success/Failure flag ("Flag" button). 2. Win32 error codes ("Win32" button). 3. HRESULT (3 "HRESULT" buttons and "Interface" button). Note: please note that HRESULT does not require COM. You don't need to initialize COM to work with HRESULT. This sample uses ComObj unit only for convenience, as it provides EOleSysError exception class with additional features for automatic safecall handling. You can write your code without ComObj unit, if you want to. HRESULT may be implemented in the following ways (all ways are illustrated in this sample): 1. Uncontrolled HRESULT (managed by RTL's safecall, 1st "HRESULT" button). 2. Customized HRESULT for routines (explicit try/except block, 2nd "HRESULT" button). 3. Customized HRESULT for methods (overriding SafeCallException method, "Interface" button). For each combination of the above mentioned method, you have to decide how you want to handle bug report for DLL exception. There are many possibilities. This sample illustrates the following: 1. Do not show bug report dialog, save bug report file. This is most common solution, it is used by "Flag", "Win32", 1st and 2nd "HRESULT" buttons. 2. Do not show bug report dialog, pass call stack to the caller. This solution is used by 3rd "HRESULT" button and "Interfaces" button (but the two buttons implement a slightly different variation). 3. Show bug report dialog AND return failure to the host. This may be a bad idea, as error will be reported twice - by DLL and by host, but this solution may work well in some specific situations. This solution is illustrated by forms DLL (use "Raise Error" button to see it in action). For more detailed information: - See source code of this sample; - See EurekaLog's help: "Advanced topics" / "Using EurekaLog in DLL" ( http://www.eurekalog.com/help/eurekalog/dll_using_eurekalog.php )