MethodBase.Invoke Method (Object, Object[])


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Invokes the method or constructor represented by the current instance, using the specified parameters.

Namespace:   System.Reflection
Assembly:  mscorlib (in mscorlib.dll)

public object Invoke(
	object obj,
	object[] parameters


Type: System.Object

The object on which to invoke the method or constructor. If a method is static, this argument is ignored. If a constructor is static, this argument must be null or an instance of the class that defines the constructor.

Type: System.Object[]

An argument list for the invoked method or constructor. This is an array of objects with the same number, order, and type as the parameters of the method or constructor to be invoked. If there are no parameters, parameters should be null.

If the method or constructor represented by this instance takes a ref parameter (ByRef in Visual Basic), no special attribute is required for that parameter in order to invoke the method or constructor using this function. Any object in this array that is not explicitly initialized with a value will contain the default value for that object type. For reference-type elements, this value is null. For value-type elements, this value is 0, 0.0, or false, depending on the specific element type.

Return Value

Type: System.Object

An object containing the return value of the invoked method, or null in the case of a constructor.


Elements of the parameters array that represent parameters declared with the ref or out keyword may also be modified.

Exception Condition

The obj parameter is null and the method is not static.


The method is not declared or inherited by the class of obj.


A static constructor is invoked, and obj is neither null nor an instance of the class that declared the constructor.


The elements of the parametersarray do not match the signature of the method or constructor reflected by this instance.


The invoked method or constructor throws an exception.


The current instance is a DynamicMethod that contains unverifiable code. See the "Verification" section in Remarks for DynamicMethod.


The parameters array does not have the correct number of arguments.


In the .NET for Windows Store apps or the Portable Class Library, catch the base class exception, MemberAccessException, instead.

The caller does not have permission to execute the method or constructor that is represented by the current instance.


The type that declares the method is an open generic type. That is, the Type.ContainsGenericParameters property returns true for the declaring type.


The current instance is a MethodBuilder.

This is a convenience method that calls the Invoke(Object, BindingFlags, Binder, Object[], CultureInfo) method overload, passing Default for invokeAttr and null for binder and culture.

If the invoked method throws an exception, the Exception.GetBaseException method returns the exception.

To invoke a static method using its MethodInfo object, pass null for obj.


If this method overload is used to invoke an instance constructor, the object supplied for obj is reinitialized; that is, all instance initializers are executed. The return value is null. If a class constructor is invoked, the class is reinitialized; that is, all class initializers are executed. The return value is null.


Starting with the .NET Framework 2.0 Service Pack 1, this method can be used to access non-public members if the caller has been granted ReflectionPermission with the ReflectionPermissionFlag.RestrictedMemberAccess flag and if the grant set of the non-public members is restricted to the caller’s grant set, or a subset thereof. (See Security Considerations for Reflection.)

To use this functionality, your application should target the .NET Framework 3.5 or later.

If a parameter of the current method is a value type, and the corresponding argument in parameters is null, the runtime passes a zero-initialized instance of the value type.

The following code example demonstrates dynamic method lookup using reflection. Note that you cannot use the MethodInfo object from the base class to invoke the overridden method in the derived class, because late binding cannot resolve overrides.

using System;
using System.Reflection;

public class MagicClass
    private int magicBaseValue;

    public MagicClass()
        magicBaseValue = 9;

    public int ItsMagic(int preMagic)
        return preMagic * magicBaseValue;

public class TestMethodInfo
    public static void Main()
        // Get the constructor and create an instance of MagicClass

        Type magicType = Type.GetType("MagicClass");
        ConstructorInfo magicConstructor = magicType.GetConstructor(Type.EmptyTypes);
        object magicClassObject = magicConstructor.Invoke(new object[]{});

        // Get the ItsMagic method and invoke with a parameter value of 100

        MethodInfo magicMethod = magicType.GetMethod("ItsMagic");
        object magicValue = magicMethod.Invoke(magicClassObject, new object[]{100});

        Console.WriteLine("MethodInfo.Invoke() Example\n");
        Console.WriteLine("MagicClass.ItsMagic() returned: {0}", magicValue);

// The example program gives the following output:
// MethodInfo.Invoke() Example
// MagicClass.ItsMagic() returned: 900


for accessing non-public members when the grant set of the non-public members is restricted to the caller's grant set, or a subset thereof. Associated enumeration: ReflectionPermissionFlag.RestrictedMemberAccess


for accessing non-public members regardless of their grant set. Associated enumeration: ReflectionPermissionFlag.MemberAccess


when invoked late-bound through mechanisms such as Type.InvokeMember. Associated enumeration: ReflectionPermissionFlag.MemberAccess.

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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