NGWS SDK Documentation  

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TypeDelegator.InvokeMember

[To be supplied.]

[Visual Basic]
Overrides Public Function InvokeMember( _
   ByVal name As String, _
   ByVal invokeAttr As BindingFlags, _
   ByVal binder As Binder, _
   ByVal target As Object, _
   ByVal args() As Object, _
   ByVal modifiers() As ParameterModifier, _
   ByVal culture As CultureInfo, _
   ByVal namedParameters() As String _
) As Object
[C#]
public override object InvokeMember(
   string name,
   BindingFlags invokeAttr,
   Binder binder,
   object target,
   object[] args,
   ParameterModifier[] modifiers,
   CultureInfo culture,
   string[] namedParameters
);
[C++]
public: override Object* InvokeMember(
   String* name,
   BindingFlags invokeAttr,
   Binder* binder,
   Object* target,
   Object* args[],
   ParameterModifier* modifiers[],
   CultureInfo* culture,
   String* namedParameters[]
);
[JScript]
public override function InvokeMember(
   name : String,
   invokeAttr : BindingFlags,
   binder : Binder,
   target : Object,
   args : Object[],
   modifiers : ParameterModifier[],
   culture : CultureInfo,
   namedParameters : String[]
) : Object;

Parameters

name
The name of the member to invoke. This may be a constructor, method, property, or field. If an empty string ("") is passed, the default member is invoked.
invokeAttr
The invocation attribute. This must be a bit flag from BindingFlags: InvokeMethod, CreateInstance, Static, GetField, SetField, GetProperty, or SetProperty. A suitable invocation attribute must be specified. If a static member is to be invoked, the Static flag must be set.
binder
An object that enables the binding, coercion of argument types, invocation of members, and retrieval of MemberInfo objects via reflection. If binder is null, the default binder is used. See Binder.
target
The object on which to invoke the specified member.
args
An argument list. This is an array of variants that contains the number, order, and type of the parameters of the member to be invoked. If the args contain an uninitialized variant, it is treated a Variant.Empty, which, with the default binder, can be widened to 0, 0.0 or String.
modifiers
An array of the same length as args with elements that represent the attributes associated with the arguments of the member to be invoked. A parameter has attributes associated with it in the member's signature. For ByRef, use ParameterModifer.ByRef and for none use ParameterModifer.None. The default binder does exact matching on these. Attributes such as In, InOut, etc. are not used in binding, they can be viewed using ParameterInfo.
culture
An instance of CultureInfo used to govern the coercion of types. If this is null, the CultureInfo for the current thread's CultureInfo is used. (Note that this is necessary to, for example, convert a String that represents 1000 to a Double value, since 1000 is represented differently by different cultures.)
namedParameters
This array of parameter names match up starting at element zero with the args array. That args[0] is matched with the parameter named namedParamaters[0] etc. There must be no "wholes" in the array. If args.Length > namedParameters.Length, the remaining parameters are filled in order.

Return Value

Returns the value of the invoked member.

Remarks

A method will be invoked if

the number of parameters in the method declaration equals the number of arguments in the specified argument list (unless default arguments are defined on the member), and

the type of each arguments can be converted by the binder to the type of the parameter.

The binder will find all of the matching methods. These methods are found based upon the type of binding requested (BindingFlags.MethodInvoke, BindingFlags.GetProperties, etc.). The set of methods is filtered by the name, number of arguments, and a set of search modifiers defined in the binder.

After the method is selected, it will be invoked. Accessibility is checked at that point. The search may control which set of methods are searched based upon the accessibility attribute associated with the method. The Binder.BindToMethod method is responsible for selecting the method to be invoked. The default binder selects the most specific match.

Note: Access restrictions are ignored for fully trusted code. That is, private constructors, methods, fields, and properties can be accessed and invoked via Reflection whenever the code is fully trusted.

Currently, InvokeMember performs the NGWS runtime reflection semantics for every type of object.

If the member specified by name is an array and the BindingFlags.GetField flag is set on invokeAttr, the args array specifies the elements whose values are to be returned. For example, the following call through Type object t returns the value of the first element of the string array MyArray, which is a member of the calling object:

String ret = (String) t.InvokeMember ("MyArray", BindingFlags.GetField, null, this, new Variant[]{0});

You can use InvokeMember to set one or more elements of a member array. All elements are set to the same value. The args array must be formatted as follows:

{index1, index2, ..., value}

For example, to set the first member of MyArray from the previous example, the syntax is as follows:

t.InvokeMember ("MyArray", BindingFlags.SetField, null, this, new Variant[]{0,"Updated"});

See Also

TypeDelegator Class | TypeDelegator Members | System.Reflection Namespace | CultureInfo