*= Operator (Visual Basic)
Multiplies the value of a variable or property by the value of an expression and assigns the result to the variable or property.
variableorproperty *= expression
The element on the left side of the *= operator can be a simple scalar variable, a property, or an element of an array. The variable or property cannot be ReadOnly (Visual Basic). The *= operator assigns the value on its right to the variable or property on its left.
Overloading
The * Operator (Visual Basic) can be overloaded, which means that a class or structure can redefine its behavior when an operand has the type of that class or structure. Overloading the * operator affects the behavior of the *= operator. If your code uses *= on a class or structure that overloads *, be sure you understand its redefined behavior. For more information, see Operator Procedures.