How to: Use Platform Invoke to Play a Wave File (C# Programming Guide) 

The following C# code example illustrates how to use platform invoke services to play a wave sound file on the Windows platform.

Example

This example code uses DllImport to import winmm.dll's PlaySound method entry point as Form1 PlaySound(). The example has a simple Windows Form with a button. Clicking the button opens a standard windows OpenFileDialog dialog box so you can open a file to play. When a wave file is selected, it is played using the PlaySound() method of the winmm.DLL assembly method. For more information on winmm.dll's PlaySound method, see Using. Browse and select a file with a .wav extension, and then click Open to play the wave file using platform invoke. A text box shows the full path of the file selected.

The Open Files dialog box is filtered to show only files with a .wav extension through the filter settings:

dialog1.Filter = "Wav Files (*.wav)|*.wav";

using System.Windows.Forms;

namespace WinSound
{
    public partial class Form1 : Form
    {
        private TextBox textBox1;
        private Button button1;

        public Form1()  //constructor
        {
            InitializeComponent();
        }

        [System.Runtime.InteropServices.DllImport("winmm.DLL", EntryPoint = "PlaySound", SetLastError = true)]
        private static extern bool PlaySound(string szSound, System.IntPtr hMod, PlaySoundFlags flags);

        [System.Flags] 
        public enum PlaySoundFlags : int
        {
            SND_SYNC = 0x0000,
            SND_ASYNC = 0x0001, 
            SND_NODEFAULT = 0x0002, 
            SND_LOOP = 0x0008, 
            SND_NOSTOP = 0x0010,
            SND_NOWAIT = 0x00002000, 
            SND_FILENAME = 0x00020000, 
            SND_RESOURCE = 0x00040004 
        }

        private void button1_Click (object sender, System.EventArgs e)
        {
            OpenFileDialog dialog1 = new OpenFileDialog(); 

            dialog1.Title = "Browse to find sound file to play";
            dialog1.InitialDirectory = @"c:\";
            dialog1.Filter = "Wav Files (*.wav)|*.wav";
            dialog1.FilterIndex = 2;
            dialog1.RestoreDirectory = true;

            if(dialog1.ShowDialog() == DialogResult.OK) 
            { 
                textBox1.Text = dialog1.FileName;
                PlaySound (dialog1.FileName, new System.IntPtr(), PlaySoundFlags.SND_SYNC);
            } 
        }
    }
}

Compiling the Code

To compile the code

1. Create a new C# Windows Application project in Visual Studio and name it WinSound.

2. Copy the code above, and paste it over the contents of the Form1.cs file.

3. Copy the following code, and paste it in the Form1.Designer.cs file, in the InitializeComponent() method, after any existing code.

   this.button1 = new System.Windows.Forms.Button();
   this.textBox1 = new System.Windows.Forms.TextBox();
   this.SuspendLayout();
   // 
   // button1
   // 
   this.button1.Location = new System.Drawing.Point(192, 40);
   this.button1.Name = "button1";
   this.button1.Size = new System.Drawing.Size(88, 24);
   this.button1.TabIndex = 0;
   this.button1.Text = "Browse";
   this.button1.Click += new System.EventHandler(this.button1_Click);
   // 
   // textBox1
   // 
   this.textBox1.Location = new System.Drawing.Point(8, 40);
   this.textBox1.Name = "textBox1";
   this.textBox1.Size = new System.Drawing.Size(168, 20);
   this.textBox1.TabIndex = 1;
   this.textBox1.Text = "FIle path";
   // 
   // Form1
   // 
   this.AutoScaleDimensions = new System.Drawing.SizeF(5, 13);
   this.ClientSize = new System.Drawing.Size(292, 266);
   this.Controls.Add(this.textBox1);
   this.Controls.Add(this.button1);
   this.Name = "Form1";
   this.Text = "Platform Invoke WinSound C#";
   this.ResumeLayout(false);
   this.PerformLayout();
   

4. Compile and run the code.

Security

For more information, see .NET Framework Security.

See Also

Tasks

Platform Invoke Technology Sample

Concepts

C# Programming Guide
Interoperability Overview (C# Programming Guide)

Other Resources

Marshaling Data with Platform Invoke