c#实现改变背景颜色、背景图片、插入背景音乐

<span style="background-color: rgb(255, 255, 255); font-family: Arial, Helvetica, sans-serif;">今天的作业苦恼了好久，特别是不知道怎么找接口，后来看了一个例子豁然开朗，试了一下自己改了下背景颜色，居然成功了！get新技能！</span>

public library()
        {
            InitializeComponent();
            SoundPlayer sp = new SoundPlayer("D:/c#/demo/demo/bin/aa.wav");//必须是带.wav扩展名的音频文件
            sp.PlayLooping();//循环播放
        }

private void button1_Click(object sender, EventArgs e)
        { 
            string[] sMystring; 
            OpenFileDialog ofdMyofd = new OpenFileDialog(); 
            ofdMyofd.FileName = "Please Select Picture"; 
            ofdMyofd.Filter = "*.jpg|*.*"; 
            if (ofdMyofd.ShowDialog() == DialogResult.OK) 
            { 
                sMystring=ofdMyofd.FileNames; 
                this.BackgroundImage = Image.FromFile(sMystring[0]); 
            }  
        }

private void button2_Click(object sender, EventArgs e)
        {
            if (colorDialog1.ShowDialog() == DialogResult.OK)
            {
                Color color = colorDialog1.Color;
                this.BackColor = color;
            }
        }