Export (0) Print
Expand All
2 out of 6 rated this helpful - Rate this topic

Convert.ChangeType Method (Object, Type)

Returns an object of the specified type and whose value is equivalent to the specified object.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)
public static Object ChangeType(
	Object value,
	Type conversionType
)

Parameters

value
Type: System.Object

An object that implements the IConvertible interface.

conversionType
Type: System.Type

The type of object to return.

Return Value

Type: System.Object
An object whose type is conversionType and whose value is equivalent to value.
-or-
A null reference (Nothing in Visual Basic), if value is null and conversionType is not a value type.
ExceptionCondition
InvalidCastException

This conversion is not supported.

-or-

value is null and conversionType is a value type.

-or-

value does not implement the IConvertible interface.

FormatException

value is not in a format recognized by conversionType.

OverflowException

value represents a number that is out of the range of conversionType.

ArgumentNullException

conversionType is null.

ChangeType is a general-purpose conversion method that converts the object specified by value to conversionType. The value parameter can be an object of any type, and conversionType can also be a Type object that represents any base or custom type. For the conversion to succeed, value must implement the IConvertible interface, because the method simply wraps a call to an appropriate IConvertible method. The method requires that conversion of value to conversionType be supported.

This method uses the current thread's culture for the conversion.

The following example illustrates the use of the ChangeType method.

using System;

public class ChangeTypeTest {
    public static void Main() {

        Double d = -2.345;
        int i = (int)Convert.ChangeType(d, typeof(int));

        Console.WriteLine("The double value {0} when converted to an int becomes {1}", d, i);

        string s = "12/12/98";
        DateTime dt = (DateTime)Convert.ChangeType(s, typeof(DateTime));

        Console.WriteLine("The string value {0} when converted to a Date becomes {1}", s, dt);        
    }
}

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
Did you find this helpful?
(1500 characters remaining)
Thank you for your feedback

Community Additions

ADD
Show:
© 2014 Microsoft. All rights reserved.