Artykuł
11/18/2011

DynamicMethod.Invoke Method (Object, BindingFlags, Binder, array<Object[], CultureInfo)

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Invokes the dynamic method using the specified parameters, under the constraints of the specified binder, with the specified culture information.

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

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Overrides Function Invoke ( _
    obj As Object, _
    invokeAttr As BindingFlags, _
    binder As Binder, _
    parameters As Object(), _
    culture As CultureInfo _
) As Object

[SecuritySafeCriticalAttribute]
public override Object Invoke(
    Object obj,
    BindingFlags invokeAttr,
    Binder binder,
    Object[] parameters,
    CultureInfo culture
)

Parameters

obj
Type: System.Object
This parameter is ignored for dynamic methods, because they are static. Specify nulla null reference (Nothing in Visual Basic).

invokeAttr
Type: System.Reflection.BindingFlags
A bitwise combination of BindingFlags values.

binder
Type: System.Reflection.Binder
A Binder object that enables the binding, coercion of argument types, invocation of members, and retrieval of MemberInfo objects through reflection. If binder is nulla null reference (Nothing in Visual Basic), the default binder is used. For more details, see Binder.

parameters
Type: array<System.Object[]
An argument list. This is an array of arguments with the same number, order, and type as the parameters of the method to be invoked. If there are no parameters this parameter should be nulla null reference (Nothing in Visual Basic).

culture
Type: System.Globalization.CultureInfo
An instance of CultureInfo used to govern the coercion of types. If this is nulla null reference (Nothing in Visual Basic), the CultureInfo for the current thread is used. For example, this information is needed to correctly convert a String that represents 1000 to a Double value, because 1000 is represented differently by different cultures.

Return Value

Type: System.Object
A Object containing the return value of the invoked method.

Exceptions

Exception	Condition
NotSupportedException	The CallingConventions.VarArgs calling convention is not supported.
TargetParameterCountException	The number of elements in parameters does not match the number of parameters in the dynamic method.
ArgumentException	The type of one or more elements of parameters does not match the type of the corresponding parameter of the dynamic method.
TargetInvocationException	The dynamic method is associated with a module, is not anonymously hosted, and was constructed with skipVisibility set to false, but the dynamic method accesses members that are not public or internal (Friend in Visual Basic). -or- The dynamic method is anonymously hosted and was constructed with skipVisibility set to false, but it accesses members that are not public.

Remarks

In addition to the listed exceptions, the calling code should be prepared to catch any exceptions thrown by the dynamic method.

Executing a dynamic method with a delegate created by the CreateDelegate method is more efficient than executing it with the Invoke method.

Calling the Invoke method or the CreateDelegate method completes the dynamic method. Any further attempt to alter the dynamic method, such as modifying parameter definitions or emitting more Microsoft intermediate language (MSIL), is ignored; no exception is thrown.

All dynamic methods are static, so the obj parameter is always ignored. To treat a dynamic method as if it were an instance method, use the CreateDelegate(Type, Object) overload to bind an object instance to a delegate.

If the dynamic method has no parameters, the value of parameters should be nulla null reference (Nothing in Visual Basic). Otherwise the number, type, and order of elements in the parameters array should be identical to the number, type, and order of parameters of the dynamic method.

Note:
This method overload is called by the Invoke(Object, array<Object[]) method overload inherited from the MethodBase class, so the preceding remarks apply to both overloads.

Examples

The following code example invokes a dynamic method with exact binding, using the US-English culture. This code example is part of a larger example provided for the DynamicMethod class.

outputBlock.Text &= vbLf & "Use the Invoke method to execute the dynamic method:" & vbLf
' Create an array of arguments to use with the Invoke method.
Dim invokeArgs() As Object = { "Mom", 42 }
' Invoke the dynamic method using the arguments. This is much
' slower than using the delegate, because you must create an
' array to contain the arguments, and value-type arguments
' must be boxed.
Dim objRet As Object = hello.Invoke(Nothing, _
    BindingFlags.ExactBinding, Nothing, invokeArgs, _
    New CultureInfo("en-us"))
outputBlock.Text &= "hello.Invoke(...) returned:  '" & objRet & "'" & vbLf

outputBlock.Text += "\r\nUse the Invoke method to execute the dynamic method:" + "\n";
// Create an array of arguments to use with the Invoke method.
object[] invokeArgs = { "Mom", 42 };
// Invoke the dynamic method using the arguments. This is much
// slower than using the delegate, because you must create an
// array to contain the arguments, and value-type arguments
// must be boxed.
object objRet = hello.Invoke(null, BindingFlags.ExactBinding, null, invokeArgs, new CultureInfo("en-us"));
outputBlock.Text += "hello.Invoke(...) returned:  '" + objRet + "'\n";

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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