Playing MP3 files

Question

I am creating a simple MP3 player for a project, and I want to make my software play mp3 sounds. I got a dropdown combobox and a play button. What I want is the selected song to play, when the play button is pushed. (After this I am also going to script pause, next and so on buttons.

Picutre of layout:

And current code for the combobox to display the song names:

namespace Jukebox___Eksamensprojekt
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void cbSange_SelectedIndexChanged(object sender, EventArgs e)
        {
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            string[] files = System.IO.Directory.GetFiles(@"C:\Programmer\Jukebox\Songs"); //Henstiller til mappen med sange

            for (int i = 0; i < files.Length; i++)
            {
                int temp = 28; //Kan ændre på tallet for at redigere hvad outputtet bliver i comboboxen
                files[i] = files[i].Substring(temp, (files[i].Length - temp)); //Sørger for jeg kun får sangnavn som output
            }

            this.cbSange.Items.AddRange(files);
        }
    }
}

EDIT: Specific question is, I have a ComboBox in which I select files (Shown in code), I also got the play button shown on the picture. What I want is, when the play button is clicked selected song will play.

EDIT. Complete code with cbSange error:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Jukebox___Eksamensprojekt
{
    public partial class Form1 : Form
    {

        public Form1()
        {
            InitializeComponent();
        }

        public class AudioItem
        {
            public string Name { get; set; }
            public string Path { get; set; }

            private void Form1_Load(object sender, EventArgs e)
            {
                this.cbSange.DisplayMember = "Name";

                var path = @"C:\Programmer\Jukebox\Songs";
                var files = System.IO.Directory.GetFiles(path);

                foreach (var file in files)
                {
                    var item = new AudioItem
                    {
                        Name = System.IO.Path.GetFileNameWithoutExtension(file),
                        Path = file
                    };
                    this.cbSange.Items.Add(item);
                }
            }

            private void cbSongs_SelectedIndexChanged(object sender, EventArgs e)
            {

                var selectedItem = cbSange.SelectedItem;
                if (selectedItem != null)
                {
                    var audioItem = (AudioItem)selectedItem;
                    var filePath = audioItem.Path;
                    //Use 'filePath' to open the file
                }
            }
        }
    }
}

Answer 1

NAudio is an audio and midi library for .NET. It has some great features including playback, volume control and visualization, should you need it.

I have used it in WinForms projects with great success. They also have some great WinForms samples inside the package. The best part is that it is opensource.

You can find the project on CodePlex

Answer 2

Here's an easy way to load and select the files in the ComboBox. First, create a class to hold the name and the path of the audio files. This way you can display the name of the file in the ComboBox but the item will (invisibly) hold the path too.

public class AudioItem
{
    public string Name {get;set;}
    public string Path {get;set;}
}

In the Load event of your Form, get the files from the folder, create an instance of the AudioItem class, set the properties accordingly and add them to the ComboBox. The first line in the Load event will set the property to display in the ComboBox, otherwise it will show something like AudioItem for every item (it's a class, not a string).

private void Form1_Load(object sender, EventArgs e)
{
    this.cbSange.DisplayMember = "Name";

    var path = @"C:\Programmer\Jukebox\Songs";
    var files = System.IO.Directory.GetFiles(path);

    foreach(var file in files)
    {
        var item = new AudioItem
        {
            Name = System.IO.Path.GetFileNameWithoutExtension(file),
            Path = file
        };
        this.cbSange.Items.Add(item);
    }
}

When the selected index of the ComboBox changes, the item will be fetched and casted to an AudioItem of which you can easily get the path. This path can be used to open and play the file.

private void cbSange_SelectedIndexChanged(object sender, EventArgs e)
{
    var selectedItem = cbSange.SelectedItem;
    if(selectedItem != null)
    {
        var audioItem = (AudioItem)selectedItem ;
        var filePath = audioItem.Path;
        //Use 'filePath' to open the file
    }
}

There is no direct built-in support to play mp3 files in .NET so I suggest you use one of the suggestions already mentioned here: NAudio, DirectX, WindowsMediaPlayer, ...

Hope this helps!

Update:

You had a mix-up in your code, it should look like this:

public class AudioItem
{
    public string Name { get; set; }
    public string Path { get; set; }
}

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        this.cbSange.DisplayMember = "Name";
        var path = @"C:\Programmer\Jukebox\Songs";
        var files = System.IO.Directory.GetFiles(path);

        foreach (var file in files)
        {
            var item = new AudioItem
            {
                Name = System.IO.Path.GetFileNameWithoutExtension(file),
                Path = file
            };
            this.cbSange.Items.Add(item);
        }
    }

    private void cbSongs_SelectedIndexChanged(object sender, EventArgs e)
    {
        var selectedItem = cbSange.SelectedItem;
        if (selectedItem != null)
        {
            var audioItem = (AudioItem)selectedItem;
            var filePath = audioItem.Path;
            //Use 'filePath' to open the file
        }
    }
}