读入图像文件并显示【C#图像处理学习笔记】

梦里梦外; 2022-05-14 23:14 266阅读 0赞

说明：

该系列读书笔记为《C\#数字图像处理算法典型事例》（赵春江 编著，人民邮电出版社，2009）读书笔记。

详细内容，请参考原始图书。

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代码如下：

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;

namespace Demo1

public partial class Form1 : Form

private string curFileName;

private System.Drawing.Bitmap curBitmap;

public Form1()

InitializeComponent();

private void Form1\_Load(object sender, EventArgs e)

private void open\_Click(object sender, EventArgs e)

OpenFileDialog opndlg = new OpenFileDialog();

opndlg.Filter = "所有文件|\*.bmp;\*.pcx;\*.png;\*.jpg;\*.gif;" +

"\*.tif;\*.ico;\*.dcx;\*.cgm;\*.cdr;\*.wmf;\*.eps;\*.emf;|" +

"位图(\*.bmp;\*.jpg;\*.png;...)|\*.bmp;\*.pcx;\*.png;\*.jpg;\*.gif;\*.tif;\*.ico|" +

"矢量图(\*.wmf;\*.eps;\*.emf;...)|\*.dcf;\*.cgm;\*.cdr;\*.wmf;\*.eps;\*.emf";

opndlg.Title = "打开图形文件";

opndlg.ShowHelp = true;

if (opndlg.ShowDialog() == DialogResult.OK)

curFileName = opndlg.FileName;

try

curBitmap = (Bitmap)Image.FromFile(curFileName);

catch (Exception exp)

MessageBox.Show(exp.Message);

Invalidate();

private void save\_Click(object sender, EventArgs e)

if (curBitmap == null)

return;

SaveFileDialog saveDlg = new SaveFileDialog();

saveDlg.Title = "保存为";

saveDlg.OverwritePrompt = true;

saveDlg.Filter = "BMP文件(\*.bmp)|\*.bmp|" + "Gif文件(\*.gif)|\*.gif|" +

"JPEG文件(\*.jpg)|\*.jpg|" + "PNG文件(\*.png)|\*.png";

saveDlg.ShowHelp = true;

if (saveDlg.ShowDialog() == DialogResult.OK)

string fileName = saveDlg.FileName;

string strFilExtn = fileName.Remove(0, fileName.Length - 3);

switch (strFilExtn)

case "bmp":

curBitmap.Save(fileName, System.Drawing.Imaging.ImageFormat.Bmp);

break;

case "jpg":

curBitmap.Save(fileName, System.Drawing.Imaging.ImageFormat.Jpeg);

break;

case "gif":

curBitmap.Save(fileName, System.Drawing.Imaging.ImageFormat.Gif);

break;

case "tif":

curBitmap.Save(fileName, System.Drawing.Imaging.ImageFormat.Tiff);

break;

case "png":

curBitmap.Save(fileName, System.Drawing.Imaging.ImageFormat.Png);

break;

default:

break;

//设定文件格式，Ctrl+E,D

private void close\_Click(object sender, EventArgs e)

this.Close();

private void Form1\_Paint(object sender, PaintEventArgs e)

Graphics g = e.Graphics;

if (curBitmap != null)

g.DrawImage(curBitmap, 160, 20, curBitmap.Width, curBitmap.Height);

结果如图：

[![clip\_image002][clip_image002]][clip_image002_clip_image002]

需要注意的问题：

在写好paint事件后，需要在窗体的事件中进行关联，开始没有关联，所以总是不能显示。

如下：

[![clip\_image004][clip_image004]][clip_image004_clip_image004]

[clip_image002]: http://hi.csdn.net/attachment/201009/20/0_12849519525EnA.gif
[clip_image002_clip_image002]: /images/20220515/158bb2aa06de486d9ae16cb8eea86c4c.png
[clip_image004]: http://hi.csdn.net/attachment/201009/20/0_1284951955AadO.gif
[clip_image004_clip_image004]: /images/20220515/4bd315877a3f4f59a700d6d7f868aa30.png