c#中设置按钮Button为透明

完全透明的按钮，只在鼠标经过时显示边框线。
属性Button.Image设置图片按钮，可与背景完美结合。

/// <summary>/// 设置透明按钮样式/// </summary>private void SetBtnStyle(Button btn){    btn.FlatStyle = FlatStyle.Flat;//样式    btn.ForeColor = Color.Transparent;//前景    btn.BackColor = Color.Transparent;//去背景    btn.FlatAppearance.BorderSize = 0;//去边线    btn.FlatAppearance.MouseOverBackColor = Color.Transparent;//鼠标经过    btn.FlatAppearance.MouseDownBackColor = Color.Transparent;//鼠标按下}private void btn_MouseHover(object sender, EventArgs e){    Button btn = sender as Button;    btn.FlatAppearance.BorderSize = 1;}private void btn_MouseLeave(object sender, EventArgs e){    Button btn = sender as Button;    btn.FlatAppearance.BorderSize = 0;}