C# Image Resizer

This program is used to resize images.

using System;
using System.Windows.Forms;
using System.Drawing;
using System.IO;
class haha
{ 
    [STAThread]
    static void Main()
    {
        string[] s=null;
        OpenFileDialog dlg = new OpenFileDialog();
        dlg.Filter = "|*.jpg";
        dlg.Multiselect = true;
        if (dlg.ShowDialog() == DialogResult.OK)
        {
            s = dlg.FileNames;
        }
        else return;
        Bitmap bit = new Bitmap(321, 241);
        for (int i = 0; i < s.Length; i++)
        {
            Graphics.FromImage(bit).DrawImage(Image.FromFile(s[i]),0,0,320,240);
            bit.Save(i + ".png");
        }
        MessageBox.Show("转换成功了");
    }
}