We use procedures and functions to create modular programs. Visual Basic statements are grouped in a block enclosed by Sub, Function and matching End statements. The difference between the two is that functions return values, procedures do not. A procedure and function is a piece of code in a larger program.
By default, Visual Studio creates a separate module file for each form in an application containing the code to construct the form. For example, the code to create a form called Form1 will be placed in a module file named Form1. Similarly, any code that has been defined by the developer to handle events from controls in the form will be placed by Visual Studio into a module file called Form1.
When writing additional Visual Basic for an application, the code should ideally be logically grouped to together with other source code in a module file.
When we say logically grouped we mean that the code should be grouped with other code of a similar nature.
For example, code to work with files might be placed in a module called FileIO. The idea is to ensure Visual Basic code is placed in a file where it makes sense for it to be located.
This will differ between applications, but it is worth investing the time to ensure code is well structured as doing so makes subsequent maintenance of the code by you or other developers much easier.
We mentioned previously that Visual Studio places the code to construct each form in separate module files. We now need to learn how to create a new module in a project to contain our own Visual Basic code.
The Add Item window will appear with the Module item pre-selected: Name the new module Math.
The new module will be added to the project and a new tab labeled Math. Now that we have added a new module to our project the next step is to add Visual Basic code to that module. Before we can do that, however, we need to learn about Visual Basic procedures.
Visual Basic Code Procedures Visual Basic procedures provide a way to break up code into logical and re-usable sections that can be called from other sections of Visual Basic code.
For example, you might have a section of Visual Basic code that calculates the interest due on a loan. It is also possible that you need to perform this calculation from a number of different places in your application code.
Rather than duplicating the code to perform this task at each code location where it is needed, it is more efficient to place the calculation code in a procedure, and then call that procedure each time it is needed. Visual Basic provides two types of procedures: It is especially useful to be able to return values from functions.
For example, the function may need to return the result of the task it performed perhaps the result of a calculation. A function might also return a True or False value to indicate when the task was performed successfully.
The Visual Basic code which called the function then acts based on the returned value. In the case of both subroutines and functions, values known as parameters may optionally be passed into the procedure. Our newly created module in Visual Studio contains the following: The syntax for a Visual Basic subroutine is as follows: Sub is the Visual Basic keyword which indicates this is a Subroutine rather than a Function.
The parameters value allows the parameters accepted by this Subroutine to be declared see below. The Public keyword indicates the scope. This defines whether this subroutine is accessible from Visual Basic code residing in other modules. Setting the scope to Private would make the Subroutine inaccessible to Visual Basic code outside the current module.
The Sub keyword indicates that this is a Subroutine as opposed to a Function and as such, does not return a value on completion.To start writing code for an event procedure, you need to double-click an object to enter the VB code window. For example, if you want to write code for the event of clicking a command button, you double-click the command button and enter the codes in the event procedure that appears in the code window, as shown in Figure You should be putting your code in the rutadeltambor.com and leave the designer file alone.
In the rutadeltambor.com[Design] you can change the properties in the properties window. If it is not currently docked to the right side of the VS designer you can show it by going to the Menu -> View . Click on the “Visual Basic” node in the tree-view on the left hand side of the dialog box and choose the "rutadeltambor.com Web Application" icon: Visual Studio will then create and open a .
You can use the power of Visual C++ in Visual Basic by creating a DLL file that includes the functions written in Visual C++.
In this tutorial, we are going to write a simple DLL that contains a function called "Message", this function allows you to show a message box. I am new to Visual Basic and am self-learning how to write rutadeltambor.com applications in Visual Studio Express.
I need someone to help me finish writing this small amount of code. Mar 02, · Theater Revenue in Visual Basic? Looking for code to this problem. show more Looking for code to this problem. Theater Revenue. A movie theater only keeps a percentage of the revenue earned from ticket sales.
The reaminder goes to the movie company. How do i Write a C++ program that converts between miles per hour (mi/h) and Status: Resolved.