Wrapping an Event Handler in a Delegate in Visual Studio .NET

Paint EAN13 in Visual Studio .NET Wrapping an Event Handler in a Delegate
Listing 314 Wrapping an Event Handler in a Delegate
Create EAN-13 In VS .NET
Using Barcode printer for ASP.NET Control to generate, create EAN 13 image in ASP.NET applications.
MyOtherComponent = function() { MyOtherComponentinitializeBase(this); this_subComponent = null; }; MyOtherComponentprototype = { _unhandledErrorOccurred: function(sender, args) { var stackTrace = args_stackTrace; if (typeof(stackTrace) != "undefined") { alert ("The Stack Trace of the error was: " + stackTrace); } },
Bar Code Generation In VS .NET
Using Barcode generation for ASP.NET Control to generate, create bar code image in ASP.NET applications.
3: Components
Make EAN 13 In .NET Framework
Using Barcode encoder for .NET Control to generate, create EAN13 image in .NET framework applications.
Listing 314 continued
Painting EAN / UCC - 14 In .NET
Using Barcode drawer for ASP.NET Control to generate, create UCC-128 image in ASP.NET applications.
initialize: function() { MyOtherComponentcallBaseMethod(this, "initialize"); this_errorHandler = $create( ErrorHandler, { id:"ApplicationErrorHandler", disableErrorPublishing: true }, { unhandledErrorOccurred: FunctioncreateDelegate ( this, this_unhandledErrorOccurred ) }, null, null); // cause an error to be thrown var nullObj = null; nullObjcauseError; } }; MyOtherComponentregisterClass("MyOtherComponent", SysComponent);
UPC-A Supplement 5 Encoder In Visual Studio .NET
Using Barcode creation for ASP.NET Control to generate, create GS1 - 12 image in ASP.NET applications.
As shown in the highlighted text, we create an instance of the Error
Barcode Creator In VS .NET
Using Barcode maker for ASP.NET Control to generate, create barcode image in ASP.NET applications.
Handler component in MyOtherComponent s initialize method When we
EAN / UCC - 13 Maker In Visual Studio .NET
Using Barcode drawer for ASP.NET Control to generate, create EAN13 image in ASP.NET applications.
assign the event handler to the unhandledErrorOccurred event, we wrap it in a delegate so that when the code goes to execute the _unhandled ErrorOccurred method it executes is using the correct context
Barcode Generator In Visual Studio .NET
Using Barcode drawer for ASP.NET Control to generate, create bar code image in ASP.NET applications.
NOTE
Paint Bar Code In VS .NET
Using Barcode maker for ASP.NET Control to generate, create barcode image in ASP.NET applications.
Functional Prefixes
EAN-8 Supplement 5 Add-On Printer In Visual Studio .NET
Using Barcode generator for ASP.NET Control to generate, create EAN8 image in ASP.NET applications.
Now that we ve covered setting properties and adding event handlers through the $create method, we can see how the property pre xes get_ and set_ and the event handler pre x add_ are not only aesthetic pre xes but also functional
Encoding Bar Code In .NET Framework
Using Barcode printer for .NET framework Control to generate, create bar code image in Visual Studio .NET applications.
SysComponent Using the references Parameter
Scanning EAN / UCC - 13 In VS .NET
Using Barcode decoder for .NET Control to read, scan read, scan image in VS .NET applications.
With the references parameter, we can assign one component to a property on another, thus linking them together You might wonder why we would need a separate parameter for this when we could already accomplish this using the properties parameter We need this parameter because when we start using server code to create instances of client components, we won t know what order the components will be created in If we use a separate parameter, the initialization process that SysApplication goes through to create our components treats component references differently and delays assigning them until all components have been created Doing this eliminates the problem of a component attempting to access an uncreated component To illustrate how to use the references parameter, we pass in one component as a reference to another component in the $create statement using the references parameter To do that, we must rst create a component that can act as a reference to our second component Listing 315 shows the two $create statements In this example, we use two ctitious components to keep the example clear
Creating Bar Code In VB.NET
Using Barcode drawer for Visual Studio .NET Control to generate, create bar code image in Visual Studio .NET applications.
Listing 315 Assigning References
Code39 Encoder In Visual Basic .NET
Using Barcode encoder for Visual Studio .NET Control to generate, create Code 39 Extended image in VS .NET applications.
// create the first component $create( MyComponent, { id: "MyFirstComponent" }, null null, null ); // create the second component and assign the first component // to a property called subComponent $create( MyComponent, { id: "MySecondComponent" }, null, { subComponent:"MyFirstComponent" }, null );
Encoding Barcode In Java
Using Barcode creation for Java Control to generate, create barcode image in Java applications.
3: Components
Print DataMatrix In Java
Using Barcode encoder for Java Control to generate, create Data Matrix ECC200 image in Java applications.
references Expected type: Object Required: No Description: An object that contains key-value pairs, where the key represents a component property, and the value represents a component to assign to this property The value is the id of the component After the $create statement has passed the event s assignment code, it processes the references parameter Similar to the properties and events parameters, the references parameter is an object that contains key-value pairs The key is the property we want to assign, and the value is an id of a component we want to assign to the property In Listing 315, the references object is highlighted The object states that we want to assign the component that has the id MyFirstComponent to the subComponent property of the component being created Just like the setProperties method we discussed earlier, the setReferences method looks for a setter method that s de ned by pre xing set_ to the property name In our example, this method s name is set_subComponent When this method is found, the component id, MyFirstComponent, is looked for within SysApplication s managed components If the component is found, the setter method is executed with the found component as its parameter
Paint USS Code 39 In .NET Framework
Using Barcode generation for .NET Control to generate, create Code 39 Extended image in Visual Studio .NET applications.
NOTE
Creating Code 3 Of 9 In Visual C#.NET
Using Barcode encoder for Visual Studio .NET Control to generate, create Code 3/9 image in Visual Studio .NET applications.
Finding Managed Components
Generate Bar Code In Java
Using Barcode encoder for Java Control to generate, create bar code image in Java applications.
Through SysApplicationfind, we can nd registered components by ID When we cover SysApplication in 4, we cover the find method in detail
Code39 Decoder In Visual Studio .NET
Using Barcode recognizer for VS .NET Control to read, scan read, scan image in .NET applications.
Creation Order
As mentioned earlier, for this code sample to work correctly, MyFirst Component must be available before the second $create statement executes References to uncreated components can be used if Sys Application is in its initialization phase This is something we cover in 4