Advanced VB: Object Oriented Programming - DLLs

Advanced VB: Object Oriented Programming - DLLs

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  Object Oriented Programming- DLLsAdvanced Visual Basic
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  OverviewA dynamic-link library(DLL) is an executable file that acts as a shared library of functions. Dynamic linking provides a way for a process to call a function that is not part of its executable code. The executable code for the function is located in a DLL, which contains one or more functions that are compiled, linked, and stored separately from the processes that use them. DLLs also facilitate the sharing of data and resources. Multiple applications can simultaneously access the contents of a single copy of a DLL in memory.
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  Where you seeDLLsDLLs (direct link libraries) are used throughout the Windows operating system. You can find many DLLs in the c:\Windows\System32 directory on your computer
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  Why use DLLs?ResearchQuestion: Why is it advantageous to use DLLs in programming?
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  Why use DLLs?DLLscan be used for many purposes including:Sharing of resourcesReduction of hard disk storage space requirementsEasier updates of applications
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  Creation of aDLLDLLs can be created easily through Visual Basic. Create a new class libraryCreate a public sub in the class library to be accessed by another applicationSaveClick Build DLLPublic Class Class1 Public Sub HelloWorld()MsgBox("Hello world") End SubEnd Class
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  Use a DLLDLLscan be used in Visual Basic by adding them as a resource to an application.Click ProjectAdd ResourceBrowse for the DLL file you createdAdd code to your application to access the DLL codePrivate Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim t As New Class1t.HelloWorld()End Sub
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  DLLsResearch Question: Wheremight you use a DLL?
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  Additional InformationFor additionalinformation about these topics, please the links provided in Blackboard.