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How to: Convert an Object to Another Type in Visual Basic

You convert an Object variable to another data type by using a conversion keyword such as CType Function.

Example

The following example converts an Object variable to an Integer and a String.

Public Sub objectConversion(ByVal anObject As Object)
    Dim anInteger As Integer
    Dim aString As String
    anInteger = CType(anObject, Integer)
    aString = CType(anObject, String)
End Sub

If you know that the contents of an Object variable are of a particular data type, it is better to convert the variable to that data type. If you continue to use the Object variable, you incur either boxing and unboxing (for a value type) or late binding (for a reference type). These operations all take extra execution time and make your performance slower.

Compiling the Code

This example requires:

  • A reference to the System namespace.

See Also

Concepts

Widening and Narrowing Conversions

Implicit and Explicit Conversions

Value Changes During Conversions

Conversions Between Strings and Other Types

Array Conversions

Typeless Programming in Visual Basic

Reference

Data Type Summary (Visual Basic)

Type Conversion Functions

Object

Other Resources

Type Conversions in Visual Basic

Structures: Your Own Data Types