大神们看看啊，为什么用openFileDialog打开的图片显示不了

[Trazen]

public partial class Form1 : Form
{
public Bitmap m_Bitmap = null;
public Form1()
{
InitializeComponent();
}

private void 打开ToolStripMenuItem_Click(object sender, EventArgs e)
{
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.Filter = "Bitmap文件(*.bmp)|*.bmp|Jpeg文件(*.Jpg)|*.jpg|所有合适的文件(*.bmp/*.jpg)|*.bmp/*.jpg";
openFileDialog.FilterIndex = 2;
openFileDialog.RestoreDirectory = true;

if (DialogResult.OK == openFileDialog.ShowDialog())
{
m_Bitmap = (Bitmap)Bitmap.FromFile(openFileDialog.FileName, false);
this.AutoScroll = true;
this.AutoScrollMinSize = new Size((int)(m_Bitmap.Width), (int)m_Bitmap.Height);
this.Invalidate();
}
private void Form1_Load(object sender, EventArgs e)
{

}

private void Form1_Paint(object sender, PaintEventArgs e)
{
Graphics gra = e.Graphics;
gra.DrawImage(m_Bitmap, new Rectangle(this.AutoScrollPosition.X, this.AutoScrollPosition.Y, (int)(m_Bitmap.Width), (int)(m_Bitmap.Height)));
}

[threenewbee]

m_Bitmap = (Bitmap)Bitmap.FromFile(openFileDialog.FileName, false); 这里下一个断点，看看有没有装载正确 gra.DrawImage(m_Bitmap, new Rectangle(this.AutoScrollPosition.X, this.AutoScrollPosition.Y, (int)(m_Bitmap.Width), (int)(m_Bitmap.Height))); 这里下一个断点，看看Paint有没有执行，以及坐标是否正确。