DLL is the abbreviation of Dynamic Link Library, meaning dynamic link library. In Windows, many applications are not a complete executable, which are split into some relatively independent dynamic link libraries, namely DLL files, placed in the system. When we perform a program, the corresponding DLL file will be called. An application can have multiple DLL files, a DLL file may also be shared by several applications, such a DLL file is called a shared DLL file. The DLL file is typically stored in the C: WindowsSystem directory. 1. How do I find out which DLL files uses the application to use the application and select the Quick View command in the shortcut menu, in the "Quick View" window of the "Quick View" window, you will see it. It uses the DLL file. 2, how to know that the DLL file is running regedit by several programs, enter the hkey_local_machinesoftwaresionshareddlls ar 查看,, 文件 文件 文件 文件 文件 文件 文件 被 子 被 被, 被 被 被 被 被 被 被 被 被 被 被 被 被 被 被Used, (2) indicates that two programs are used, (0) indicates no program, can be deleted. 3, how to solve the loss of the DLL files Sometimes when the file is uninstalling, reminds you that a DLL file may affect the operation of other applications. So when you uninstall the software, you may have misleave the shared DLL file. Once there is a loss of the DLL file, if you can determine its name, you can find the DLL file in the sysbckup (System Backup Folder), and copy it to the System folder. If this is not, "*** DLL file loss ..." prompt box always appears when the computer starts, you can run Msconfig in "Start / Run", after entering the System Configuration Utility dialog, click Select "System.ini" tab, find a prompt lost DLL file, so that it does not appear when it is turned on. -------------------------------------------------- ------------------------ Use the VB Activex.dll file in the ASP. No one will work in a more troublesome method without necessary. Unless there is room for no choice. So if I want to tell you that there is a simple technology to make your ASP development faster, and more efficient, you must be particularly interested. This approach will transfer from most of your business logic from your ASP page to a Visual Basic ActiveX .dll to achieve performance of the entire web page. The reason for using ActiveX .dll is created in Visual Basic. DLL file is actually an ActiveX object. This object can be implemented using Microsoft's Component Object Model (COM) technology, you can also use them to create classes related to .dll. Developers have used .DLL has many reasons, and each project will not contain all the advantages. However, once you use this method, you find that you use ActiveX .dll technology. Let us now look at the superiority of using ActiveX .dll technology. Better performance has no doubt, a major problem with a developer is a complete performance. Compared to a normal ASP page, an ActiveX .dll runs faster. Let's take a look at a simple example. A ASP page calculates a variable from 0 to 10000000, then displaying a "DONE" string requires 26,087 milliseconds. However, VB.dll files can complete this process only 100 milliseconds. So Vb.dll is 260 times faster than ASP pages.
In such a test, the difference in speed is obvious because the ASP runs for 26 seconds, and only less than 1 second. Remember, the difference in speed is mainly related to the workload to be processed by the code, that is, the larger the workload of the code is, the more obvious the difference in speed. If the above test file is doubled, the speed difference will be more obvious. The ASP page requires 25,156 milliseconds, however .dll only takes 70 milliseconds - the latter runs at a speed of 359 times. .dll has two: .dll compiled compared to the ASP page. This means that the file is run in the machine language, which reaches the speed it can achieve. The ASP page is running the code that is processed by a script engine, so that each part must be compiled and then processed. .dll uses a variable that is declared as a long integer data type, which does not require an explanation of 32-bit processors. The script page is used by a Variant variable, which must be converted into a number before it can be used in the calculation, which inevitably increases the processing time. Variable declaration methods Better variable declarations can make running more rapid, in addition to this, can be more easily developed because variable types do not need to be converted. Variables can be declared in the initial state to avoid writing additional conversion code rows. Source code is hidden. DLL file allows you to hide your source code and prevent it from attacking by some hackers. A ASP page stores the script to your web server in plain text. Once someone gets access to your network site file, the web page is easily accessed, so your source code is disclosed and damaged. Use a normal ActiveX.dll file to handle your site's business logic, so that you can prevent uncomfortable people to access your source code. More enriching from the development environment You can also use Microsoft's script editor to develop ASP scripts. Although this is also a comparative function complete tool, it only provides basic scripting features. Instead, Visual Basic is a rich development environment. In short, these two tools are not comparable - one is the script tool and the other is a fully functional development package. Higher efficiency cross-developments are easily applicable to other development environments, such as Microsoft Access. On the other hand, when cross-development with other environments, developers must re-establish an ASP page task. Higher efficiency ASP Pages One containing all Business logic can become very lengthy. The .dll file is a very efficient solution because it contains all the logic. This management result is: more simple and efficient code. Some disadvantages For most, the advantage of using ActiveX .dll is overcome, but you should remember that there are still some shortcomings. First, ActiveX .dll will result in more development time in some cases. For example, it takes approximately two seconds in variable calculations, but the ASP page only needs one second. However, this is not very obvious in the start stage. A set of organized and reusable ActiveX .dll classes used in the final phase can shorten your development time. Second, a typical ASP page is easy to change: You only need to add scripts and save files. Updating a .DLL is quite complex with the ASP page, because you can't compile .dll without restarting the web server. However, as a universal rule, you can simplify the web server and then compile or copy a new .dll when the server is running again. Restarting the server only one second, so there is no interrupt. Third, running time must be established in the web server. If you use an ActiveX .dl in an ASP page, but do not install the VB runtime, you can simply use the Package and Development Wizard to install all the procedures.
