ArcEngine中使用上下左右键移动地图

转自愿文ArcEngine中使用上下左右键移动地图

因项目需要，需对mapcontrol控件响应上下左右键，从网上找的方法都一样，都值提到了需要设置axMapControl1的KeyIntercept属性为1，但这样做的结果是，除了自己在onkeydown中设置的平移1/10个屏幕大小外，系统还会有一个默认的平移操作。经研究发现，设置axMapControl1的autokeyboardscrolling属性为false即可屏蔽系统默认的对上下左右键的相应方法。

axMapControl1.AutoKeyBoardScrolling=false;
axMapControl1.KeyIntercept = ;
private void axMapControl1_OnKeyDown(object sender, ESRI.ArcGIS.MapControl.IMapControlEvents2_OnKeyDownEvent e)
{
    switch (e.keyCode)
    {
        case (int)System.Windows.Forms.Keys.Up:
            PanMap(0d, 0.5d);
            break;
        case (int)System.Windows.Forms.Keys.Down:
            PanMap(0d, -0.5d);
            break;
        case (int)System.Windows.Forms.Keys.Left:
            PanMap(-0.5d, 0d);
            break;
        case (int)System.Windows.Forms.Keys.Right:
            PanMap(0.5d, 0d);
            break;
    }
}  

private void PanMap(double ratioX, double ratioY)
{
    //Pans map by amount specified given in a fraction of the extent e.g. rationX=0.5, pan right by half a screen
    IEnvelope envelope = axMapControl1.Extent;
    double h = envelope.Width;
    double w = envelope.Height;
    envelope.Offset(h * ratioX, w * ratioY);
    axMapControl1.Extent = envelope;
}