&= Operator (Visual Basic)
Concatenates a String expression to a String variable or property and assigns the result to the variable or property.
variableorproperty &= expression
Parts
variableorproperty
Required. Any String variable or property.expression
Required. Any String expression.
Remarks
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 concatenates the String expression on its right to the String variable or property on its left, and assigns the result 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 (Visual Basic).
Example
The following example uses the &= operator to concatenate two String variables and assign the result to the first variable.
Dim var1 As String = "Hello "
Dim var2 As String = "World!"
var1 &= var2
' The value of var1 is now "Hello World!".
See Also
Reference
Assignment Operators (Visual Basic)
Concatenation Operators (Visual Basic)
Operator Precedence in Visual Basic
Operators Listed by Functionality (Visual Basic)