1.界面上拖个.pictureBox(pictureBox1)
//上传点击按钮
 private void button1_Click(object sender, EventArgs e)
 {
 OpenFileDialog fileDialog = new OpenFileDialog();
 DialogResult result = fileDialog.ShowDialog();
 if (result == DialogResult.OK)
 {
 this.pictureBox1.Image = Image.FromFile(fileDialog.FileName);
 }
 }
//清楚图片按钮
 private void button2_Click(object sender, EventArgs e)
 {
 this.pictureBox1.Image = null;
 }
C#--程序背景图片设置
 public Form1()
 {
 InitializeComponent();
 this.pictureBox1.BackgroundImage = Image.FromFile(@"C:\Users\admin\Desktop\logo.png");
 this.BackgroundImageLayout = ImageLayout.Stretch;//自动伸展
 }