Channels ▼

Web Development

Your Own MP3 Duration Calculator

The App Class

The App class is generated by Visual Studio if you use it (I do). The code is split across two files: One of them is called App.g.cs and you can find it in the Debug/obj folder, but don't modify it. The other file is called App.xaml.cs and you can find it in the project folder. In this file you can add application-level event handlers like OnStartup() and OnExit(). In this case it is pretty trivial:

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Windows;

namespace MP3DurationCalculator
  /// <summary>
  /// Interaction logic for App.xaml
  /// </summary>
  public partial class App : Application

The two files are merged to a single class by the virtue of the partial class feature of C#. In addition to the code files there is also the application XAML file called App.xaml. This file contains a couple of namespaces, identifies the application class (MP3DurationCalculator.App and the URI of the main windows's XAML file. WPF takes it from here and knows how to instantiate the App and display the main window.

<Application x:Class="MP3DurationCalculator.App"

Related Reading

More Insights

Currently we allow the following HTML tags in comments:

Single tags

These tags can be used alone and don't need an ending tag.

<br> Defines a single line break

<hr> Defines a horizontal line

Matching tags

These require an ending tag - e.g. <i>italic text</i>

<a> Defines an anchor

<b> Defines bold text

<big> Defines big text

<blockquote> Defines a long quotation

<caption> Defines a table caption

<cite> Defines a citation

<code> Defines computer code text

<em> Defines emphasized text

<fieldset> Defines a border around elements in a form

<h1> This is heading 1

<h2> This is heading 2

<h3> This is heading 3

<h4> This is heading 4

<h5> This is heading 5

<h6> This is heading 6

<i> Defines italic text

<p> Defines a paragraph

<pre> Defines preformatted text

<q> Defines a short quotation

<samp> Defines sample computer code text

<small> Defines small text

<span> Defines a section in a document

<s> Defines strikethrough text

<strike> Defines strikethrough text

<strong> Defines strong text

<sub> Defines subscripted text

<sup> Defines superscripted text

<u> Defines underlined text

Dr. Dobb's encourages readers to engage in spirited, healthy debate, including taking us to task. However, Dr. Dobb's moderates all comments posted to our site, and reserves the right to modify or remove any content that it determines to be derogatory, offensive, inflammatory, vulgar, irrelevant/off-topic, racist or obvious marketing or spam. Dr. Dobb's further reserves the right to disable the profile of any commenter participating in said activities.

Disqus Tips To upload an avatar photo, first complete your Disqus profile. | View the list of supported HTML tags you can use to style comments. | Please read our commenting policy.