C# 小技巧
WPF自定义按键实现窗口的关闭、最小化和拖动
1 private void Grid_MouseMove(object sender, MouseEventArgs e)
2 {
3 if (e.LeftButton == MouseButtonState.Pressed) this.DragMove();
4 }
5
6 private void ItmMin_Click(object sender, RoutedEventArgs e)
7 {
8 this.WindowState = WindowState.Minimized;
9 }
10
11 private void ItmClose_Click(object sender, RoutedEventArgs e)
12 {
13 this.Close();
14 }
自定义类有时需要通过类似数组下标方式访问数据 (例：x = a[i,j] ) 可以定义索引器，和访问器比较类似：
1 public CplxNumber this[int x, int y]//x,y是下标，在函数内当做参数使用
2 {
3 get
4 {
5 if (x <= 0 || y <= 0 || x > _height || y > _width) return null;
6 else return new CplxNumber(_data[(x - 1) * _width * 2 + (y - 1) * 2], _data[(x - 1) * _width * 2 + (y - 1) * 2 + 1]);
7 }
8 set
9 {
10 if (x <= 0 || y <= 0 || x > _height || y > _width) return;
11 else { _data[(x - 1) * _width * 2 + (y - 1) * 2] = value.Real; _data[(x - 1) * _width * 2 + (y - 1) * 2 + 1] = value.Imag; }
12 }
13 }
运算符重载，也是比较常用的的小技巧，形式是 public static <type> opeartor <opeartor >(<type> a,<type> b) 示例如下：
1 public static CplxNumber operator *(CplxNumber c1,CplxNumber c2)
2 {
3 return new CplxNumber(c1.Real*c2.Real-c1.Imag*c2.Imag,c1.Real*c2.Imag+c1.Imag*c2.Real);
4 }
通过窗口打开和保存文件
1 /// <summary>
2 /// 弹出文件选择窗口获得选择文件
3 /// </summary>
4 /// <returns></returns>
5 private BitmapSource GetSource()
6 {
7 BitmapSource result = null;
8
9 OpenFileDialog dialog = new OpenFileDialog();
10 dialog.Title = "打开图片";
11 dialog.Filter = "常用位图(*.bmp;*.jpg;*.png)|*.bmp;*.jpg;*.png";
12
13 if (true == dialog.ShowDialog() && File.Exists(dialog.FileName))
14 {
15 FileStream imageStreamSource = File.OpenRead(dialog.FileName);
16 BitmapDecoder decoder = BitmapDecoder.Create(imageStreamSource, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
17 result = decoder.Frames[0];
18 }
19
20 return result;
21 }
22
23 private void OutPut_Click(object sender, RoutedEventArgs e)
24 {
25
26 SaveFileDialog dialog = new SaveFileDialog();
27 dialog.Filter = "图片(*.jpg)|*.jpg";
28 dialog.FileName = Title;
29 dialog.Title = "保存图片";
30
31 if (dialog.ShowDialog() == true)
32 {
33 // 利用JpegBitmapEncoder，对图像进行编码，以便进行保存
34 JpegBitmapEncoder encoder = new JpegBitmapEncoder();
35 encoder.Frames.Add(BitmapFrame.Create(_image));
36 // 保存文件
37 FileStream fileStream = new FileStream(dialog.FileName, FileMode.Create, FileAccess.ReadWrite);
38 encoder.Save(fileStream);
39 // 关闭文件流
40 fileStream.Close();
41
42 MessageBox.Show("保存成功！");
43 }
44 }
