ArcGis For Silverlight API,地图显示Gis,绘制点，线，绘制图等--绘制点、线、圆，显示提示信息

ArcGis For Silverlight API,地图显示Gis,绘制点，线，绘制图等--绘制点、线、圆，显示提示信息

/// <summary>
/// 绘制界面上的点和线
/// </summary>
/// <param name="myMap"></param>
/// <param name="point"></param>
/// <param name="pointLine"></param>
public void DrawAnimationCompleted(Map myMap, List<Graphic> point,ESRI.ArcGIS.Client.Geometry.PointCollection pointLine)
{
    GraphicsLayer gPointLayer = new GraphicsLayer();
    GraphicsLayer lineLayer = new GraphicsLayer();
    SimpleLineSymbol lineSymbol = new SimpleLineSymbol();
    lineSymbol.Color = new SolidColorBrush(Colors.Brown);
    lineSymbol.Width = 1;
    lineSymbol.Style = SimpleLineSymbol.LineStyle.Solid;

    // 画线到图层上并绘制到地图上
    GisMap.AddLayersToMap(myMap, new GraphicsLayer[] { lineLayer });
    GisLine.DrawLineOnMap(pointLine, lineLayer, lineSymbol);

    GisMap.DrawAllLayers(myMap, new GraphicsLayer[] { gPointLayer }, point);
    GisMap.AddLayersToMap(myMap, new GraphicsLayer[] { gPointLayer });
}

好，看一下如何画圆吧。

/// <summary>
/// 在地图上绘制圆
/// </summary>
/// <param name="myMap">地图</param>
/// <param name="container">绘制容器</param>
/// <param name="pt">要绘制的点</param>
/// <param name="drawCircleLayer"></param>
/// <param name="circleKm">直径</param>
/// <param name="color">填充色</param>
/// <param name="ellipseStroke">边框色</param>
public void DrawEllipse(Map myMap, Canvas container, MapPoint pt,ref ElementLayer drawCircleLayer, double circleKm,Color color,Color ellipseStroke)
{
    if (!drawCircleLayer.Children.Contains(container))
    {
        drawCircleLayer.Children.Add(container);
        container.Opacity = 0.5;
        container.SetValue(ElementLayer.EnvelopeProperty, new Envelope(myMap.Extent.XMax, myMap.Extent.YMax, myMap.Extent.XMin, myMap.Extent.YMin));
    }

    Point ptFirst = myMap.MapToScreen(new MapPoint(Convert.ToDouble(pt.X),
        Convert.ToDouble(pt.Y)));

    Point pt7 = myMap.MapToScreen(new MapPoint((Convert.ToDouble(pt.X) + circleKm * kmToEN),
        Convert.ToDouble(pt.Y)));

    Ellipse ellipse7 = new Ellipse();
    ellipse7.Width = (pt7.X - ptFirst.X) * 2;
    ellipse7.Height = ellipse7.Width;
    ellipse7.StrokeThickness = 1;
    ellipse7.Stroke = new SolidColorBrush(ellipseStroke);
    ellipse7.Fill = new SolidColorBrush(color);
    Canvas.SetLeft(ellipse7, ptFirst.X - ellipse7.Width / 2);
    Canvas.SetTop(ellipse7, ptFirst.Y - ellipse7.Width / 2);
    ellipse7.Opacity = 0.5;

    container.Children.Add(ellipse7);
    container.IsHitTestVisible = false;
    container.SetValue(Canvas.ZIndexProperty, -10);
}

这是一个画圆的方法，需要地图类，点，Canvas容器,Gis 的地图层ElementLayer和color

我前台是这样调用的

 {                GisMap.DeleteLayersToMap(myMap, "WindCircleLayer");            }

            ElementLayer circleLayer = new ElementLayer();
            circleLayer.ID = "WindCircleLayer";

            Canvas circleCanvas = new Canvas();

            Graphic tipGraphic = sender as Graphic;

            if (Convert.ToDouble(tipGraphic.Attributes["WindCircle7"]) != 0)
            {
                Color color = new Color();
                color.A = 255;
                color.R = 153;
                color.G = 105;
                color.B = 192;

                DrawEllipse(myMap, circleCanvas, new MapPoint(Convert.ToDouble(tipGraphic.Attributes["Longitude"]),
                    Convert.ToDouble(tipGraphic.Attributes["Latitude"])), ref circleLayer,
                    Convert.ToDouble(300), color, Colors.Blue);

            }

            if (Convert.ToDouble(tipGraphic.Attributes["WindCircle10"]) != 0)
            {
                Color color = new Color();
                color.A = 255;
                color.R = 111;
                color.G = 91;
                color.B = 171;

                this.DrawEllipse(myMap, circleCanvas, new MapPoint(Convert.ToDouble(tipGraphic.Attributes["Longitude"]),
                    Convert.ToDouble(tipGraphic.Attributes["Latitude"])), ref circleLayer,
                    Convert.ToDouble(tipGraphic.Attributes["WindCircle10"]), color, Colors.Blue);
            }


            GisMap.AddLayersToMap(myMap, new ElementLayer[] { circleLayer });
        }

这里的sender是一个Gis元素 Graphic,根据我的WebService 取到的实体后我把这个点加上了Attributes，一系列属性，所以在上面的代码可以看到tipGraphic.Attributes["WindCircle10"],

 

下面的代码就是在我从WebService取到实体后做添加点的代码:

/// <summary>
/// 添加台风点代码
/// 添加鼠标移入、移出事件
/// </summary>
/// <param name="model"></param>
/// <param name="i"></param>
private void AddPointToGraphic(TyphoonModel model, int i, List<Graphic> pointParam)
{
    SimpleMarkerSymbol symbol = new SimpleMarkerSymbol();
    Color color = new Color();
    color.A = 255;

    if (Convert.ToDouble(model.WS) <= 17.1)
    {
        color.R = 0;
        color.G = 254;
        color.B = 223;
        symbol.Color = new SolidColorBrush(color);
    }
    else if (Convert.ToDouble(model.WS) > 17.1 && Convert.ToDouble(model.WS) <= 24.4)
    {
        color.R = 254;
        color.G = 243;
        color.B = 0;
        symbol.Color = new SolidColorBrush(color);
    }
    else if (Convert.ToDouble(model.WS) > 24.4 && Convert.ToDouble(model.WS) <= 32.6)
    {
        color.R = 254;
        color.G = 144;
        color.B = 44;
        symbol.Color = new SolidColorBrush(color);
    }
    else if (Convert.ToDouble(model.WS) > 32.6 && Convert.ToDouble(model.WS) <= 41.4)
    {
        color.R = 254;
        color.G = 4;
        color.B = 4; symbol.Color = new SolidColorBrush(color);
    }
    else if (Convert.ToDouble(model.WS) > 41.4 && Convert.ToDouble(model.WS) <= 50.9)
    {
        color.R = 254;
        color.G = 58;
        color.B = 163; symbol.Color = new SolidColorBrush(color);
    }
    else if (Convert.ToDouble(model.WS) > 50.9)
    {
        color.R = 174;
        color.G = 0;
        color.B = 217; symbol.Color = new SolidColorBrush(color);
    }

    symbol.Size = 10;
    if (i == 0)
    {
        symbol.Style = SimpleMarkerSymbol.SimpleMarkerStyle.Square;
    }
    else
    {
        symbol.Style = SimpleMarkerSymbol.SimpleMarkerStyle.Circle;
    }

    pointParam.Add(new Graphic()
    {
        Geometry = new MapPoint(model.Longitude, model.Latitude),
        Symbol = symbol
    });

    pointParam[i].Attributes.Add("TyphoonID", model.TyphoonID);
    pointParam[i].Attributes.Add("TyphoonNo", model.TyphoonNo);
    pointParam[i].Attributes.Add("TyphoonName", model.TyphoonName);
    pointParam[i].Attributes.Add("WindCircle7", model.WindCircle7);
    pointParam[i].Attributes.Add("WindCircle10", model.WindCircle10);
    pointParam[i].Attributes.Add("WS", model.WS);
    pointParam[i].Attributes.Add("Pressure", model.Pressure);
    pointParam[i].Attributes.Add("IssueTime", model.IssueTime);
    pointParam[i].Attributes.Add("Future", model.Future);
    pointParam[i].Attributes.Add("Latitude", model.Latitude);
    pointParam[i].Attributes.Add("Longitude", model.Longitude);
}

信息提示功能如图:

 

 

我们先看下Xmal中的代码:

<Canvas x:Name="typhoonPointInfoCanvas" Visibility="Visible" Height="188" HorizontalAlignment="Left" Margin="0,-272,0,0" VerticalAlignment="Top" Width="360">
    <Path Stretch="Fill" Stroke="Black"  Height="168.5" Width="328.5" UseLayoutRounding="False" Canvas.Left="0.5" Canvas.Top="-0.5" Data="M113,25 C113,11.745166 123.74516,1.0000004 137,1.0000004 L304,1.0000004 C317.25482,1.0000004 328,11.745166 328,25 L328,144 C328,157.25484 317.25482,168 304,168 L137,168 C123.74516,168 113,157.25484 113,144 z M112.5,24.499998 L0.5,0.5 L112.5,72.499992 z" Fill="{StaticResource CommonGradient2}"/>

    <StackPanel Orientation="Vertical" Height="168" Width="176" Canvas.Left="137" Canvas.Top="15">
        <TextBlock x:Name="typhoonNameTextBlock" Height="20" Text="名称:" Foreground="White" TextWrapping="Wrap"/>
        <TextBlock x:Name="typhoonCollectionTimeTextBlock" Height="20" Text="时间:" Foreground="White" TextWrapping="Wrap" d:LayoutOverrides="HorizontalAlignment"/>
        <TextBlock x:Name="typhoonPositionTextBlock" Height="20" Text="位置:" Foreground="White" TextWrapping="Wrap" d:LayoutOverrides="HorizontalAlignment"/>
        <TextBlock x:Name="typhoonWSTextBlock" Height="20" Text="最大风速:" Foreground="White" TextWrapping="Wrap" d:LayoutOverrides="HorizontalAlignment"/>
        <TextBlock x:Name="typhoonPressureTextBlock" Height="20" Text="中心气压:" Foreground="White" TextWrapping="Wrap" d:LayoutOverrides="HorizontalAlignment"/>
        <TextBlock x:Name="typhoonCircle7TextBlock" Height="20" Text="7级风圈半径:" Foreground="White" TextWrapping="Wrap" d:LayoutOverrides="HorizontalAlignment"/>
        <TextBlock x:Name="typhoonCircle10TextBlock" Height="20" Text="10级风圈半径:" Foreground="White" TextWrapping="Wrap" d:LayoutOverrides="HorizontalAlignment"/>

    </StackPanel>
</Canvas>

  <LinearGradientBrush x:Key="CommonGradient" StartPoint="0.5,0" EndPoint="0.5,1">            <GradientStop Offset="0" Color="#ee76a8d3"/>            <GradientStop Offset="0.25" Color="#ee5b8cb5"/>            <GradientStop Offset="0.75" Color="#ee4b7ba7"/>        </LinearGradientBrush

看下c# 中的代码:

当我们添加那些点也就是 Graphic 的时候有这样一个事件MouseEventHandler

// 添加点和线，先显示点层，动画结束后显示线层
mapDraw.DrawLineAndPoint(ref point, myMap, gLayer, ref pointLine, e, length);


// 添加点事件
foreach (Graphic item in point)
{
    item.MouseEnter += new MouseEventHandler(MainPage_MouseEnter);
    item.MouseLeave += new MouseEventHandler(MainPage_DrawLine);
}

/// <summary>
/// 绘制单条台风动画前的信息
/// </summary>
/// <param name="point"></param>
/// <param name="myMap"></param>
/// <param name="gLayer"></param>
/// <param name="pointLine"></param>
/// <param name="e"></param>
/// <param name="length"></param>
public void DrawLineAndPoint(ref List<Graphic> point,Map myMap,GraphicsLayer gLayer,
   ref ESRI.ArcGIS.Client.Geometry.PointCollection pointLine, GetTyphoonsCompletedEventArgs e, int length)
{
    #region 添加点代码
    point = new List<Graphic>();
    for (int i = 0; i < length; i++)
    {
        AddPointToGraphic(e.Result[i], i, point);
    }
    #endregion

    // 添加线的代码
    pointLine = new ESRI.ArcGIS.Client.Geometry.PointCollection();
    AddLineToMap(e.Result.ToList(), length, pointLine);

    // 显示点层
    GisMap.DrawAllLayers(myMap, new GraphicsLayer[] { gLayer }, point);
    GisMap.AddLayersToMap(myMap, new GraphicsLayer[] { gLayer });
}

 AddPointToGraphic这个方法就是图片上面的那段代码

<SPAN style="FONT-SIZE: 14px"> item.MouseEnter += new MouseEventHandler(MainPage_MouseEnter);     </SPAN>

item.MouseLeave += new MouseEventHandler(MainPage_DrawLine);

这两段代码就是我们添加鼠标移入和移出事件了，我们看下移入事件:

<DIV class=cnblogs_Highlighter><PRE class=brush:csharp>        void MainPage_MouseEnter(object sender, MouseEventArgs e)
        {
            Graphic graphic = sender as Graphic;
            Cursor = Cursors.Hand;

            typhoonPointInfoCanvas.Visibility = Visibility.Visible;

            Point pt = myMap.MapToScreen(new MapPoint(Convert.ToDouble(graphic.Attributes["Longitude"]), Convert.ToDouble(graphic.Attributes["Latitude"])));

            typhoonPointInfoCanvas.SetValue(Grid.MarginProperty, new Thickness(pt.X, pt.Y, 0, 0));

            typhoonNameTextBlock.Text = "台风：" + graphic.Attributes["TyphoonName"].ToString();
            typhoonCollectionTimeTextBlock.Text = "时间：" + graphic.Attributes["IssueTime"].ToString();
            typhoonPositionTextBlock.Text = "位置：" + graphic.Attributes["Longitude"].ToString() + "°E," + graphic.Attributes["Latitude"].ToString() + "°N";
            typhoonWSTextBlock.Text = "最大风速：" + graphic.Attributes["WS"].ToString() + " m/s";
            typhoonPressureTextBlock.Text = "中心气压：" + graphic.Attributes["Pressure"].ToString() + " hPa";
            typhoonCircle7TextBlock.Text = "7级风圈半径：" + graphic.Attributes["WindCircle7"].ToString() + " km";
            typhoonCircle10TextBlock.Text = "10级风圈半径：" + graphic.Attributes["WindCircle10"].ToString() + " km";

            circle.DrawEllipse7And10WindCircle(myMap, sender);
            selectedGarphic = sender as Graphic;
        }</PRE>
</DIV>

我们看到在显示信息的同时我们又把圆画了上去<SPAN style="FONT-SIZE: 14px">DrawEllipse7And10WindCircle()这个函数</SPAN>
GisMap是个静态类，以下是他的代码

/// <summary>
/// ArcGis 调用类
/// 动态加载、显示隐藏层数据、加载层上的点等
/// 日期：2010-5-10
/// 作者：AngelSoft
/// </summary>
public static class GisMap
{

    /// <summary>
    /// 绘制所有的点到地图上
    /// </summary>
    /// <param name="glayer"></param>
    /// <param name="cacheGraphic"></param>
    public static void DrawSymbol(GraphicsLayer glayer, List<Graphic> cacheGraphic)
    {
        if (glayer != null)
        {
            int graphicCount = cacheGraphic.Count;
            for (int i = 0; i < graphicCount; i++)
            {
                glayer.Graphics.Add(cacheGraphic[i]);
            } // i
        }
    }

/// <summary>
/// 加载所有图层上的点
/// 动态绘制
/// 图层和点的对应关系要正确
/// 有几个图层就要有几个点集合
/// </summary>
/// <param name="map">ArcGis 地图变量</param>
/// <param name="layers">GraphicLayer 层数组</param>
/// <param name="graphicParam">Graphic 点数组</param>
public static void DrawLayers(Map map, GraphicsLayer[] layers, params List<Graphic>[] graphicParam)
{
    // 计算要绘制的层数并一层一层的绘制(调用动态绘制方法)
    if (layers != null)
    {
        int length = layers.Length;
        for (int i = 0; i < length; i++)
        {
            if (layers[i] == null)
            {
                layers[i] = new GraphicsLayer();
            }
            DynamicDrawSymbol(layers[i], graphicParam[i], map);
        }
    }
}


/// <summary>
/// 加载所有图层上的点
/// 画所有点
/// 图层和点的对应关系要正确
/// 有几个图层就要有几个点集合
/// </summary>
/// <param name="map">ArcGis 地图变量</param>
/// <param name="layers">GraphicLayer 层数组</param>
/// <param name="graphicParam">Graphic 点数组</param>
public static void DrawAllLayers(Map map, GraphicsLayer[] layers, params List<Graphic>[] graphicParam)
{
    // 计算要绘制的层数并一层一层的绘制(调用动态绘制方法)
    if (layers != null)
    {
        int length = layers.Length;
        for (int i = 0; i < length; i++)
        {
            if (layers[i] == null)
            {
                layers[i] = new GraphicsLayer();
            }
            DrawAllGraphics(layers[i], graphicParam[i]);
        }
    }
}



/// <summary>
/// 隐藏或显示 ArcGis 层
/// </summary>
/// <param name="show">隐藏或显示</param>
/// <param name="layers">层</param>
public static void LayersVisibility(bool show, params GraphicsLayer[] layers)
{
    if (layers != null)
    {
        foreach (GraphicsLayer item in layers)
        {
            item.Visible = show;
        }
    }
}


/// <summary>
/// 将图层数组全部从 map 中移除
/// </summary>
/// <param name="map">表示一张 ArcGis 地图</param>
/// <param name="layers">表示地图层的数组</param>
public static void DeleteLayersToMap(Map map, GraphicsLayer[] layers)
{
    // 逐个将数据移除
    foreach (GraphicsLayer item in layers)
    {
        map.Layers.Remove(item);
    }
}

/// <summary>
/// 根据 ID 号删除某层
/// </summary>
/// <param name="map"></param>
/// <param name="ID"></param>
/// <returns></returns>
public static void DeleteLayersToMap(Map map, string[] ID)
{
    int length = ID.Length;

    for (int i = 0; i < length; i++)
    {
        foreach (Layer item in map.Layers)
        {
            if (item.ID == ID[i])
            {
                map.Layers.Remove(item);
                length--;
                break;
            }
        }
    }
}

/// <summary>
/// 将图层数组全部从 map 中移除
/// </summary>
/// <param name="map">表示一张 ArcGis 地图</param>
/// <param name="layers">表示地图层的数组</param>
public static void DeleteLayersToMap(Map map, ElementLayer[] layers)
{
    // 逐个将数据移除
    foreach (ElementLayer item in layers)
    {
        map.Layers.Remove(item);
    }
}


/// <summary>
/// 删除地图上的某一层
/// </summary>
/// <param name="myMap"></param>
/// <param name="ID">ID号</param>
public static void DeleteLayersToMap(Map myMap, string ID)
{
    int layers = myMap.Layers.Count;
    for (int i = 0; i < layers; i++)
    {
        if (myMap.Layers[i].ID == ID)
        {
            myMap.Layers.RemoveAt(i);
            return;
        }
    }
}


public static bool LayerExist(Map myMap, string ID)
{
    int layers = myMap.Layers.Count;
    for (int i = 0; i < layers; i++)
    {
        if (myMap.Layers[i].ID == ID)
        {
            return true;
        }
    }
    return false;
}


/// <summary>
/// 将图层数组全部添加到 map 中
/// </summary>
/// <param name="map">表示一张 ArcGis 地图</param>
/// <param name="layers">表示地图层的数组</param>
public static void AddLayersToMap(Map map, GraphicsLayer[] layers)
{
    // 逐个将数据添加到当前地图中
    foreach (GraphicsLayer item in layers)
    {
        if (item != null)
        {
            map.Layers.Add(item);
        }
    }
}

/// <summary>
/// 将图层数组全部添加到 map 中
/// </summary>
/// <param name="map">表示一张 ArcGis 地图</param>
/// <param name="layers">表示地图层的数组</param>
public static void AddLayersToMap(Map map, ElementLayer[] layers)
{
    // 逐个将数据添加到当前地图中
    foreach (ElementLayer item in layers)
    {
        map.Layers.Add(item);
    }
}

/// <summary>
/// 绘制所有的点到地图上
/// </summary>
/// <param name="eLayer"></param>
/// <param name="image"></param>
public static void AddImageToElementLayer(ElementLayer eLayer, List<Image> image)
{
    if (eLayer != null)
    {
        foreach (Image item in image)
        {
            eLayer.Children.Add(item);
        }
    }
}

/// <summary>
/// 隐藏或显示 ArcGis 层
/// </summary>
/// <param name="show">隐藏或显示</param>
/// <param name="layers">层</param>
public static void LayersVisibility(bool show, params ElementLayer[] layers)
{
    if (layers != null)
    {
        foreach (ElementLayer item in layers)
        {
            item.Visible = show;
        }
    }
}

/// <summary>
/// 动态加载图层
/// 使用 ElementLayer 层
/// </summary>
/// <param name="eLayer"></param>
/// <param name="cacheGraphic"></param>
/// <param name="map"></param>
public static void DynamicDrawElementLayer(ElementLayer eLayer, List<UIElement> cacheElement, Map map)
{
    // 以下四个变量分别表示地图的四个边
    // 即最大经纬度和最小经纬度
    // xMax最大经度,yMax最大纬度
    double xMax = map.Extent.XMax + 2;
    double xMin = map.Extent.XMin - 2;
    double yMax = map.Extent.YMax + 2;
    double yMin = map.Extent.YMin - 2;

    // 去除不在坐标范围内的点,先检查图层是否为空
    if (eLayer != null)
    {
        int graphicCount = eLayer.Children.Count;
        for (int i = 0; i < graphicCount; i++)
        {
            UIElement element = eLayer.Children[i];

            // 判断经度,纬度
            if (!(((element.GetValue(ElementLayer.EnvelopeProperty) as Envelope).Extent.XMax < xMax && (element.GetValue(ElementLayer.EnvelopeProperty) as Envelope).Extent.XMax > xMin)
                && ((element.GetValue(ElementLayer.EnvelopeProperty) as Envelope).Extent.YMax < yMax && (element.GetValue(ElementLayer.EnvelopeProperty) as Envelope).Extent.YMax > yMin)))
            {
                // 将点在地图上移除,并放在缓存中
                cacheElement.Add(eLayer.Children[i]);
                eLayer.Children.Remove(eLayer.Children[i]);
                graphicCount--;   // 当从集合中移除元素时应该把 graphicCount 减1
                i--;              // 元素被移除后相当于当前元素的后一位元素会 -1,应该再循环一次本次循环所以应该 -1
            }
        } // i
    }

    // 检查缓存是否为空,并将点绘制到图形上
    if (cacheElement != null)
    {
        int count = cacheElement.Count;
        for (int i = 0; i < count; i++)
        {
            // 判断经度,纬度
            if (((cacheElement[i].GetValue(ElementLayer.EnvelopeProperty) as Envelope).Extent.XMax < xMax && (cacheElement[i].GetValue(ElementLayer.EnvelopeProperty) as Envelope).Extent.XMax > xMin)
                && ((cacheElement[i].GetValue(ElementLayer.EnvelopeProperty) as Envelope).Extent.YMax < yMax && (cacheElement[i].GetValue(ElementLayer.EnvelopeProperty) as Envelope).Extent.YMax > yMin))
            {
                // 运行到此则该点在目前地图范围内,将该点加入到地图中
                eLayer.Children.Add(cacheElement[i]);
                cacheElement.Remove(cacheElement[i]);
                count--;    // 当从集合中移除元素时应该把 count 减1
                i--;        // 元素被移除后相当于当前元素的后一位元素会 -1,应该再循环一次本次循环所以应该 -1
                continue;
            }
        }
    }
}

/// <summary>
/// 将所有元素画到地图上
/// </summary>
/// <param name="eLayer"></param>
/// <param name="cacheElement"></param>
public static void DrawAllUIElement(ElementLayer eLayer, List<UIElement> cacheElement)
{
    if (eLayer != null)
    {
        foreach (UIElement item in cacheElement)
        {
            eLayer.Children.Add(item);
        }
    }
}

/// <summary>
/// 动态的绘制图层
/// 当然地图移动到相应的坐标后绘制(保留原来的点,绘制新的数据)
/// 实现了无刷新绘制
/// </summary>
/// <param name="glayer">表示地图上的层</param>
/// <param name="cacheGraphic">存放 Graphics 的缓存</param>
/// <param name="map">表示一张 ArcGis 地图</param>
private static void DynamicDrawSymbol(GraphicsLayer glayer, List<Graphic> cacheGraphic, Map map)
{
    // 以下四个变量分别表示地图的四个边
    // 即最大经纬度和最小经纬度
    // xMax最大经度,yMax最大纬度
    double xMax = map.Extent.XMax + 2;
    double xMin = map.Extent.XMin - 2;
    double yMax = map.Extent.YMax + 2;
    double yMin = map.Extent.YMin - 2;

    // 去除不在坐标范围内的点,先检查图层是否为空
    if (glayer != null)
    {
        int graphicCount = glayer.Graphics.Count;
        for (int i = 0; i < graphicCount; i++)
        {
            // 判断经度,纬度
            if (!((glayer.Graphics[i].Geometry.Extent.XMax < xMax && glayer.Graphics[i].Geometry.Extent.XMax > xMin)
                && (glayer.Graphics[i].Geometry.Extent.YMax < yMax && glayer.Graphics[i].Geometry.Extent.YMax > yMin)))
            {
                // 将点在地图上移除,并放在缓存中
                cacheGraphic.Add(glayer.Graphics[i]);
                glayer.Graphics.Remove(glayer.Graphics[i]);
                graphicCount--;   // 当从集合中移除元素时应该把 graphicCount 减1
                i--;              // 元素被移除后相当于当前元素的后一位元素会 -1,应该再循环一次本次循环所以应该 -1
            }
        } // i
    }

    // 检查缓存是否为空,并将点绘制到图形上
    if (cacheGraphic != null)
    {
        int count = cacheGraphic.Count;
        for (int i = 0; i < count; i++)
        {
            // 判断经度,纬度
            if ((cacheGraphic[i].Geometry.Extent.XMax < xMax && cacheGraphic[i].Geometry.Extent.XMax > xMin)
                && (cacheGraphic[i].Geometry.Extent.YMax < yMax && cacheGraphic[i].Geometry.Extent.YMax > yMin))
            {
                // 运行到此则该点在目前地图范围内,将该点加入到地图中
                glayer.Graphics.Add(cacheGraphic[i]);
                cacheGraphic.Remove(cacheGraphic[i]);
                count--;    // 当从集合中移除元素时应该把 count 减1
                i--;        // 元素被移除后相当于当前元素的后一位元素会 -1,应该再循环一次本次循环所以应该 -1
                continue;
            }
        }
    }
}

/// <summary>
/// 将所有元素画到地图上
/// </summary>
/// <param name="eLayer"></param>
/// <param name="cacheElement"></param>
private static void DrawAllGraphics(GraphicsLayer eLayer, List<Graphic> cacheGraphic)
{
    if (eLayer != null)
    {
        foreach (Graphic item in cacheGraphic)
        {
            eLayer.Graphics.Add(item);
        }
    }
}

今天把 GisMap 这个类都写出来了也为了我写下一篇文章做准备吧！后面会写一篇动态加载数据点的文章！因为当大批量点(2000)左右加载到地图上的时候，

就会非常的卡，基本都动不了，所以我们要动态去加载这些点。