Visual Basic/Windows API
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[edit] Windows API
APIs, short for "application programming interface", allows you to access a wide array of functions and methods exposed by the operating system or other applications (DLLs), performing operations not normally implemented by the standard virtual machine that Visual Basic provides. This includes operations such as shutting down the computer or listing all the current running processes.
[edit] Declaration
An example of a declaration is the GetTickCount function which returns the amount of milliseconds that have elapsed since Windows was started. To use it, insert the following into a standard module in your project:
Public Declare Function GetTickCount Lib "kernel32.dll" () As Long
To access it, simply call it like you would call any normal function. Note, however, that this is a Public declaration and is limited to modules. If you don't need it to be accessible in your entire project, use the Private declaration and insert it in the class module or form directly:
Private Declare Function GetTickCount Lib "kernel32.dll" () As Long
[edit] Resources
For a beginner it is normally difficult to create a declare statement since it requires knowing how to map C datatypes to Visual basic datatypes. There is a built in program that comes along with VB6 called API Text Viewer which lists all commonly used API functions, contants and types. A VB programmer can just find the required function from said program and insert into the VB module.
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