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This article mainly shows you "how to use VB.NET overload", the content is easy to understand, clear, hope to help you solve your doubts, the following let the editor lead you to study and learn "how to use VB.NET overload" this article.

VB.NET overloading means that we can declare methods with the same name multiple times in a class, as long as each declaration has a different parameter list.

Different parameter lists mean different types of data types in the list. Now let's take a look at the following method declaration:

Public Sub MyMethod (X As Integer, Y As Integer)

The parameter list for this method can be seen as (integer,integer). In order to overload this method, we must use different parameter lists, such as (integer,double). Of course, you can also change the order of data types, for example, (integer,double) and (double,integer) are different, these two are also overloaded. Overloading cannot be achieved simply by changing the return type of the function, but by requiring different data types of parameters.

As an example, if we want to provide a search function and return a set of data based on some criteria, the specific code should be:

Public Function MyFindData (ByVal Name As String) As ArrayList (search data and return results) End Function

In VB 6, if we want to add a new search option based on some criteria, we must add a function with a different name, that is, VB 6 does not have the ability to overload. But now in VB.NET, we can simply overload existing functions, much like Visual C++.

Public Overloads Function FindData (ByVal Name As String) As ArrayList (search data and return results) End Function Public Overloads Function FindData (ByVal Age As Integer) As ArrayList (search data and return results) End Function

If you look closely, you can see that the declarations of both methods have the same method name. This doesn't work in VB 6, which requires each method to have a different name. However, methods with the same name are allowed in the VB.NET overload, but the parameter requirements are different. It is worth mentioning that the Overloads keyword is added to every declaration.

When overloading a method, we can use the scope keywords of Public, Friend, and so on to make it have a different scope, as long as we use different parameter lists. This means that we can change the MyFindData method to have a different scope:

Public Overloads Function FindData (ByVal Name As String) As ArrayList (search data and return results) End Function Friend Overloads Function FindData (ByVal Age As Integer) As ArrayList (search data and return results) End Function

With this change, other code in the VB.NET project can use MyFindData. MyFindData only needs to receive an integer data as a parameter.

The above is all the contents of the article "how to use VB.NET reload". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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