1732: Implementing a Custom Dynamic Object in Visual C#

Make Quick Response Code in Visual C# 1732: Implementing a Custom Dynamic Object
Listing 1732: Implementing a Custom Dynamic Object
Making QR-Code In Visual C#.NET
Using Barcode encoder for .NET framework Control to generate, create QR Code image in VS .NET applications.
using System; using SystemDynamic; using SystemXmlLinq; public class DynamicXml : DynamicObject { private XElement Element { get; set; } public DynamicXml(SystemXmlLinqXElement element) { Element = element; } public static DynamicXml Parse(string text) { return new DynamicXml(XElementParse(text));
Generate Barcode In C#
Using Barcode drawer for Visual Studio .NET Control to generate, create barcode image in VS .NET applications.
Programming with Dynamic Objects
QR Code Drawer In Visual Studio .NET
Using Barcode creation for ASP.NET Control to generate, create QR Code ISO/IEC18004 image in ASP.NET applications.
} public override bool TryGetMember( GetMemberBinder binder, out object result) { bool success = false; result = null; XElement firstDescendant = ElementDescendants(binderName)FirstOrDefault(); if (firstDescendant != null) { if (firstDescendantDescendants()Count() > 0) { result = new DynamicXml(firstDescendant); } else { result = firstDescendantValue; } success = true; } return success; } public override bool TrySetMember( SetMemberBinder binder, object value) { bool success = false; XElement firstDescendant = ElementDescendants(binderName)FirstOrDefault(); if (firstDescendant != null) { if (valueGetType() == typeof(XElement)) { firstDescendantReplaceWith(value); } else { firstDescendantValue = valueToString(); } success = true; } return success; } }
QR Code Generator In .NET Framework
Using Barcode encoder for .NET framework Control to generate, create QR Code 2d barcode image in VS .NET applications.
The key dynamic implementation methods for this use case are TryGetMember() and the TrySetMember() (assuming you also want to assign the
Making QR-Code In Visual Basic .NET
Using Barcode generation for VS .NET Control to generate, create QR Code image in Visual Studio .NET applications.
elements as well) Only these two method implementations are necessary
Barcode Encoder In Visual C#
Using Barcode generation for Visual Studio .NET Control to generate, create barcode image in .NET framework applications.
17: Reflection, Attributes, and Dynamic Programming
Bar Code Generator In Visual C#.NET
Using Barcode maker for VS .NET Control to generate, create bar code image in .NET framework applications.
to support the invocation of the dynamic getter and setter properties Furthermore, the implementations are straightforward First, they examine the contained XElement, looking for an element with the same name as the binderName the name of the member invoked If a corresponding XML element exists, then the value is retrieved (or set) The return value is set to true if the element exists and false if it doesn t Automatically, a return value of false will cause the runtime to throw a MicrosoftCSharpRuntimeBinderRuntimeBinderException at the call site of the dynamic member invocation SystemDynamicDynamicObject supports additional virtual methods if additional dynamic invocations are required Listing 1733 shows the list of all the overridable members
Generating Code-39 In C#.NET
Using Barcode printer for Visual Studio .NET Control to generate, create Code 39 Full ASCII image in .NET applications.
Listing 1733: Overridable Members on SystemDynamicDynamicObject
Creating Code128 In C#
Using Barcode encoder for .NET Control to generate, create Code-128 image in VS .NET applications.
using SystemDynamic; public class DynamicObject : IDynamicMetaObjectProvider { protected DynamicObject(); public virtual IEnumerable<string> GetDynamicMemberNames(); public virtual DynamicMetaObject GetMetaObject( Expression parameter); public virtual bool TryBinaryOperation( BinaryOperationBinder binder, object arg, out object result); public virtual bool TryConvert( ConvertBinder binder, out object result); public virtual bool TryCreateInstance( CreateInstanceBinder binder, object[] args, out object result); public virtual bool TryDeleteIndex( DeleteIndexBinder binder, object[] indexes); public virtual bool TryDeleteMember( DeleteMemberBinder binder); public virtual bool TryGetIndex( GetIndexBinder binder, object[] indexes, out object result); public virtual bool TryGetMember( GetMemberBinder binder, out object result); public virtual bool TryInvoke( InvokeBinder binder, object[] args, out object result); public virtual bool TryInvokeMember(
Data Matrix Generator In Visual C#.NET
Using Barcode printer for .NET Control to generate, create DataMatrix image in VS .NET applications.
Summary
EAN128 Creator In VS .NET
Using Barcode encoder for Visual Studio .NET Control to generate, create EAN / UCC - 14 image in .NET applications.
InvokeMemberBinder binder, object[] args, out object result); public virtual bool TrySetIndex( SetIndexBinder binder, object[] indexes, object value); public virtual bool TrySetMember( SetMemberBinder binder, object value); public virtual bool TryUnaryOperation( UnaryOperationBinder binder, out object result); }
Code 39 Full ASCII Creation In Java
Using Barcode generation for Java Control to generate, create Code 3/9 image in Java applications.
As Listing 1733 shows there are member implementations for everything from casts and various operations, through to index invocations In addition, there is a method for retrieving all the possible member names: GetDynamicMemberNames()
ANSI/AIM Code 128 Creator In Java
Using Barcode generation for Java Control to generate, create Code 128B image in Java applications.
SUMMARY
Barcode Creator In .NET
Using Barcode drawer for ASP.NET Control to generate, create bar code image in ASP.NET applications.
This chapter discussed how to use reflection to read the metadata that is compiled into the CIL Using reflection, you saw how to provide a late binding in which the code to call is defined at execution time rather than at compile time Although reflection is entirely feasible for deploying a dynamic system, it is considerably slower than statically linked (compiletime), defined code This tends to make it more prevalent and useful in development tools Reflection also enables the retrieval of additional metadata decorating various constructs in the form of attributes Typically, custom attributes are sought using reflection It is possible to define your own custom attributes that insert additional metadata of your own choosing into the CIL At runtime, it is then possible to retrieve this metadata and use it within the programming logic Many view attributes as a precursor to a concept known as aspectoriented programming, in which you add functionality through constructs such as attributes instead of manually implementing the functionality wherever it is needed It will take some time before you see true aspects within C# (if ever); however, attributes provide a clear steppingstone in that direction, without forcing a significant risk to the stability of the language
Draw USS Code 39 In VB.NET
Using Barcode generator for .NET Control to generate, create Code-39 image in VS .NET applications.
Draw Code128 In .NET Framework
Using Barcode printer for .NET framework Control to generate, create Code-128 image in Visual Studio .NET applications.
Drawing GS1 - 13 In VS .NET
Using Barcode generator for .NET Control to generate, create GTIN - 13 image in Visual Studio .NET applications.
ECC200 Printer In .NET
Using Barcode drawer for Visual Studio .NET Control to generate, create ECC200 image in .NET applications.