.NET/ASP.NET/C#/VB.NET PDF Document SDK

The first step of soldering a component to the PCB is making absolutely sure that you have the component leads in the right holes and that the part is oriented properly. If you have built the circuit on the breadboard first, it s a simple matter of pulling parts off the breadboard and placing them one by one. Push the leads of a component through the holes and spread the leads apart, as shown in Figure A-10, to keep the component from falling out when you turn the PCB over to solder. You can work on one part at a time, but the job will go faster if you place several parts that are close together at the same time and then solder.

barcode add-in for word and excel 2010, barcode generator excel macro, barcode font in excel, free barcode addin for excel 2007, barcode in excel free download, barcode addin for excel 2007, excel barcodes not working, how to create barcode in excel using barcode font, barcode software excel 2007, free barcode macro excel 2007,

Listing 8-5. weatherTable.jsp <%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> <table> <tbody> <tr> <c:forEach var="forecast" items="${forecastData.details.weatherData}"> <td> ${forecast.day} <br/> High: ${forecast.maxTemperatureF} <br/> Low: ${forecast.minTemperatureF} <br/> <img src="${forecast.weatherImage}" alt="forecast image"/> </td> </c:forEach> </tr> </tbody> </table> The code for the weatherLocation.jsp file is rather simple. It uses the Java Standard Tag Library (JSTL) to dynamically fill in the city name and state of the weather forecast. In weatherTable.jsp, JSTL tags iterate over an array of weather data objects, where each weather data object encapsulates the forecast information for a particular day. For each weather data object, a table cell is rendered that displays the high and low temperatures along with an image describing the expected cloud cover. By now you must be wondering: where does Ajax fit in You ll now look at how the Ajax request is sent to the server. The following function, which appears in the weatherForecast.js file, uses the Taconite framework to send the request for a weather forecast for a particular ZIP code: function updateWeatherForecast() { var ajaxRequest = new AjaxRequest("UpdateWeatherForecast"); ajaxRequest.addFormElementsById("forecastZipCode"); ajaxRequest.sendRequest(); } The first thing you should notice is that the body of the updateWeatherForecast method is only three lines long. In comparison, the example from 4, which also sends a single parameter as part of the request, is 28 lines long, counting only the code that actually creates the XMLHttpRequest object, creates the query string, and sends the response. The AjaxRequest object is the heart of the Taconite framework s browser-side functional3565005953993bd3170c41194f12907b ity. The AjaxRequest object encapsulates its own instance of the XMLHttpRequest object, so multiple instances of AjaxRequest do not share the same instance of an XMLHttpRequest

When accessing methods within a class, they will usually call the version of the method in the most derived class. That means if you try to call a method on the base class and it has been overridden by the derived class, then it will automatically call the version on the derived class. Ordinarily this is used to call the base implementation of a method you are overriding. This isn t always necessary but generally is required by library design guidelines because it can lead to the base class malfunctioning if you do not do this. To get access to methods on the base class, you give the base class a name. You do this by using the keyword as after the name of the class you are inheriting from, followed by the name you want to give to the base class. This name then acts like the keyword base in C#, giving you access to the base class s methods. The following example shows an implementation of a class that derives from System. Windows.Form. The identifier base is assigned to base class Form, as shown at the top of the definition of the MySquareForm class. The example uses implicit class construction, indicated by the fact that the type MySquareForm takes a parameter, color. open System.Drawing open System.Windows.Forms type MySquareForm(color) = class inherit Form() as base override x.OnPaint(e) = e.Graphics.DrawRectangle(color, 10, 10, x.Width - 30, x.Height - 50) base.OnPaint(e) override x.OnResize(e) = x.Invalidate() base.OnResize(e) end

Figure A-10. Placement of the component on a PC board To make a solder joint, touch the soldering iron tip to both the PCB copper pad and the component wire at the same time and allow the connection to heat for a second. Figure A-11 shows the proper placement of the soldering iron tip and the lead.

let form = new MySquareForm(Pens.Blue) do Application.Run(form) In this form you override two methods, OnPaint and OnResize, and in these methods you use the identifier base, which grants access to the base class, to call the base class s implementation of this method.