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Explaining ByVal and ByRef in Visual Basic

In Visual Basic, the difference between a variable declared as ByVal and ByRef lies in how the argument is passed in a procedure.

ByVal

When a variable is declared as ByVal, a copy of the variable's value is passed to the procedure. This means any changes made to the variable within the procedure do not affect the original variable outside the procedure.

Example of using ByVal: Passing a constant value to a procedure where the original value should not be modified.

ByRef

When a variable is declared as ByRef, a reference to the variable is passed to the procedure. This allows the procedure to directly modify the original variable's value.

Example of using ByRef: When you want to modify the original variable's value inside a procedure and reflect those changes outside the procedure as well.

Choosing between ByVal and ByRef in Visual Basic depends on whether you want to preserve the original value of the variable or allow changes to reflect outside the procedure.

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Focus keyword: Visual Basic