C#实现鼠标滚筒缩放界面的效果

elementCanvas继承UserControl

声明属性：

#region 缩放属性添加
float ratio = 1.0f;
public float Ratio
{
set
{
ratio = value;

Width = width;
Height = height;
}
get => ratio;
}

int width;

public int Width
{
set
{
width = value;
Console.WriteLine("W::" + width + "width+Value::" + width * Ratio);
base.Width = (int)(width * Ratio);

}
get
{
return width;
}
}

int height;

public int Height
{
set
{
height = value;
base.Height = (int)(height * Ratio);
}
get
{
return height;
}
}

#endregion

添加鼠标事件：

 this.MouseWheel += new MouseEventHandler(this_MouseWheel);

private void this_MouseWheel(object sender, MouseEventArgs e)
{
if (Control.ModifierKeys == Keys.Control)
{
if (e.Delta > 0)
Ratio += 0.1f;
else if (e.Delta < 0)
Ratio -= 0.1f;
Ratio = Ratio > 0.3f ? Ratio : 0.3f;
Ratio = Ratio < 2.0f ? Ratio : 2.0f;
}
}