如何设置图片的选择框，有代码，请指正
private void picfortype_Click(object sender, EventArgs e)
{
Image imge = ((PictureBox)sender).Image;



Image imge = ((PictureBox)sender).Image;
int newheight = imge.Height;
int newwidth = imge.Width;

Pen myPen = new Pen(Brushes.Black, 2);

myPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dot;

Bitmap bmp = new Bitmap(newwidth, newheight);
Graphics g = Graphics.FromImage(bmp);

Rectangle rec = new Rectangle(0, 0, newwidth, newheight);

g.DrawImage(imge, rec, 0, 0, imge.Width, imge.Height, GraphicsUnit.Pixel);
g.DrawRectangle(myPen, 0, 0, newwidth, newheight);

((PictureBox)sender).Image = bmp;

//pictureBox1.Image = bmp;
//textBox1.Text = ((PictureBox)sender).Tag.ToString();


}

这个是picturebox的单击事件

我的目的：我已经在tabcontrol的tabpage里面动态生成了几个picturebox控件，也加载好了图片。
现在我点击每个图片，需要在当前点击的图片加一个边框，代表选中的意思。
以上代码已经实现了增加边框，但是我点每个图片都加了边框
我是想只让我当前点击的有边框，当我点击下一个图片的时候，点击的目标有边框，前面的有边框的取消。意思就是不论多少个图片，当前只能有一个有边框



[解决办法]
private PictureBox picPrev=null; //上一次加边框的图片控件
private Image imgPrev=null; //上一次图片控件的图片
private void picfortype_Click(object sender, EventArgs e)
{
Image imge = ((PictureBox)sender).Image;


Image imge = ((PictureBox)sender).Image;
int newheight = imge.Height;
int newwidth = imge.Width;

Pen myPen = new Pen(Brushes.Black, 2);

myPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dot;

Bitmap bmp = new Bitmap(newwidth, newheight);
Graphics g = Graphics.FromImage(bmp);

Rectangle rec = new Rectangle(0, 0, newwidth, newheight);

g.DrawImage(imge, rec, 0, 0, imge.Width, imge.Height, GraphicsUnit.Pixel);
g.DrawRectangle(myPen, 0, 0, newwidth, newheight);

((PictureBox)sender).Image = bmp;

//pictureBox1.Image = bmp;
//textBox1.Text = ((PictureBox)sender).Tag.ToString();

if(picPrev!=null)
{
picPrev.Image=imgPrev;
}
picPrev=((PictureBox)sender;
imgPrev=imge;
}