Multimedia programming with VB has a strong VB (Visual Basic) with strong multimedia processing control, VB multimedia control MCI (Media Control Interface) includes a set of commands that control audio and video devices but have unrelated to devices, with it It is very convenient to carry out multimedia design. For example: You may want to have a CD player you have written, then use VB's MCI only need to write a few lines of code, you can generate a fully fully equipped CD player. The following simply talks about the preliminary knowledge of multimedia design with VB's MCI and gives an example of a very simple CD player. Multimedia devices such as sound cards, CD-ROMs, etc., and drivers of these devices must be installed before using MCI, otherwise MCI will not listen to the command. I. MCI control installation MCI control is different in VB different versions. In VB 3.0 Professional, the MCI control file is MCI.vbx, and the MCI control file in VB 4.0 is MCI16.ocx (16-bit), MCI32.ocx (32-bit). In general, MCI control is not added to the toolbox after starting VB (Toolbox), you need to do it yourself. 1. MCI installation in VB 3.0. Open the VB's File menu, select the add file item, find MCI.vbx from the Windows / System directory, select OK, then you will find that Toolbox finally one tool, this is MCI. If you often use it, it is recommended to find the autoload.mak file in the VB directory. Use the word processing software to open it, add MCI.vbx to it, so that it will be automatically transferred each time you start VB. 2. The installation of MCI in VB 4.0. VB 4.0 supports 16-bit and 32-bit systems, and only 16-bit systems can be used under Windows 3.1. MCI cannot be tuned in VB 3.0, if you do this will find system prompt errors, you need to transfer it in the AutoLoad.mak file. After the author opens the autoload.mak file, it is found that the call format is: Object = {serial number} # 1.0 # 0; file name, I don't know the serial number of MCI16.ocx can't be installed. Fortunately, there is a subdirectory of MCI under the subdirectory Sample under the VB directory. Enter it can see there is a mcitest.mak file, open it. You can see: object = {C1A8AF28-1257-101B-8FB0-0020AF039CA3} # 1.0 # 0; MCI32.oCX is a row (maybe your serial number is not necessarily the same), copy this line to the AutoLoad.mak file. Since I use Windows 3.1, when I install VB 4.0, 32-bit systems cannot be loaded, the hard disk does not have the mci32.ocx file, why use MCI32.ocx to transfer? The test found that VB selection files in serial numbers, may be the serial number of the MCI16.ocx file, and further experiments have found that even if the MCI32.ocx behind the serial number is removed, it further illustrates an OCX in VB 4.0. The file has a corresponding serial number, so absolutely cannot change the serial number, otherwise it will not be able to transfer the desired file correctly. The MCI is installed, double-click the MCI icon of the toolbox with the mouse, and if there is 9 familiar twists in Form, the installation is successful. Second, MCI's attributes and event MCI offers many properties and events on MCI control. The comparison commonly used properties are: Button Visible determines whether the button is visible in MCI control. The MCI command to be executed, such as Open Close Play Stop Eject, etc.
