Silverlight客户端实现区域像元统计以及地形剖面图的绘制

开始之前的一段废话:

放假回家了也就没有写博客了,家里没有网,偶尔也只能用手机上一上,看一看是否有新的评论和回复,是否有和我研究相关的博文和动态。今天是三月一号,学校的校园网帐号解封了,于是便把寒假部分的工作内容总结一下,在此也和大家一起分享我的心得,希望对各位读者能有所帮助。

本文的例子是我帮一位兄弟做的,算起还是我的学长,只不过不同学校,具体的要求如下:

http://bbs.esrichina-bj.cn/ESRI/viewthread.php?tid=124221&extra=page%3D1

于是假期的时候便做了一个该功能的例子,然后还加了一点小功能。后面的文章中将会详细介绍,下面就进入正题吧!

一、本文实现的功能

1.1 要素查询功能

根据要素属性,查询出相应的要素

1.2 栅格数据的像元统计

例如输入一个几何图形(点,线,面)可以计算出该图像范围内栅格数据的像元信息,如:像元最大值,最小值,以及平均值等,具体如下图所示:                  

       

 1.3 绘制地形剖面图

 该功能和官网的这个例子差不多:

http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#SurfaceProfile

(不知道为什么,我这里查看不了这里例子)

效果如下图所示:

二、使用到的数据和知识

2.1地图数据

        本例的地形高程数据来自于国际科学数据服务平台,下载网址:

http://datamirror.csdb.cn/index.jsp

        本例的各区县要素数据来自于国家基础地理信息中心,下载网址:

http://nfgis.nsdi.gov.cn/nfgis/chinese/c_xz.htm

上面的地图是我自己在ArcMap中制作的一张地图,外加了一点地形阴影效果,这是在ArcMap中的图层列表

 

各县面要素图层

       

 最后通过以上数据得到了本文使用的底图。在查询部分中,实际上查询的就是各区县的面要素,可通过输入曲线的民称或编号来查询出相对应的县,然后再通过调研像元统计的GP服务工具,即可实现像元统计,得到对应区县范围内像元的最大值,最小值等信息,实际上这里的值也就是对应区县的海拔(准确度由下载的高程数据所决定),最后的地图:

2.2 使用到如下的知识:

2.2.1 要素的属性查询

2.2.2 GP服务的调用

2.2.3 通过开源的Silverlight图表控件:OxyPlot

以上前两部分内容都在之前的博文中讲过,所以不是本文的重点。关于OxyPlot图表控件也很简单,这里不会过多的解释说明。官网有很好的帮助文档。

三、实现过程

3.1 查询(要素属性查询和空间查询)

可参考之前的博文:

http://www.cnblogs.com/potential/archive/2013/01/31/2882244.html

3.2 根据查询得到的面要素,计算出面要素对应区域内的像元信息。

3.2.1  发布像元统计的GP服务

这里主要用到的就是GP服务。下面是本文的GP服务模型:

 

其中ZoneFiled就是统计字段,InputFeature为输入的要素,ZonalRaster为统计的删格数据

提醒:在10.1中可以将栅格数据作为输入参数。在10.0中不可以,如果您是10.0版本的,那么这里你只能在建模的时候指定栅格数据,然后去掉设置为模型参数。在10.1中如果你有可数的几个不同栅格数据,那么你可以将其添加到ArcMap中,在发布GP服务的时候,会提示你从列表选择还是自定义栅格数据,这个时候你可以选择从列表选择。然后你可以将ArcMap中的删格数据图层添加到选择列表中,最后在Web端调用的时候,你只需要输入栅格数据列表中对于栅格数据的名称即可,例如本文的列表如下:

 

这里可以看出只有一个栅格数据选项:hunandata。

3.2.2   Web端调用GP服务

调用GP服务的过程之前的博文也有讲到,可参考这里:

http://www.cnblogs.com/potential/archive/2012/11/03/2752289.html

下面是本文的调用代码:

 private void AccessGPService(FeatureSet featureset)
        {
            List<GPParameter> gppara = new List<GPParameter>();
            //输入GP服务的参数
            gppara.Add(new GPString("ZoneFiled", "OBJECTID"));
            gppara.Add(new GPFeatureRecordSetLayer("InputFeature", featureset));
            gppara.Add(new GPString("ZonalRaster", "hunandata"));
            _geoprocessor.SubmitJobAsync(gppara);
        }

        private void _geoprocessor_JobCompleted(object sender, JobInfoEventArgs e)
        {
            HttpWebRequest.RegisterPrefix("http://", System.Net.Browser.WebRequestCreator.ClientHttp);
            Geoprocessor gp = sender as Geoprocessor;
            //请求GP服务的结果
            gp.GetResultDataAsync(e.JobInfo.JobId, "ResultTable");
        }

        private void _geoprocessor_GetResultDataCompleted(object sender, GPParameterEventArgs e)
        {
            MyDataGrid.ItemsSource = null;
            GPRecordSet gpr = e.Parameter as GPRecordSet;
            if (gpr.FeatureSet != null)
            {
                for (int i = 0; i < gpr.FeatureSet.Features.Count; i++)
                {
                    for (int j = 2; j < gpr.FeatureSet.Features[i].Attributes.Count; j++)
                    {
                        //这里本文有个Bug,就是当FeatureDataGrid绑定到GraphicsLayer后,
                        //如果修改GrapicsLayer的属性(增加或者删除)会报错,以下代码不能通过,所以这里选择了先修改再绑定
                        List<string> keyList = gpr.FeatureSet.Features[i].Attributes.Keys.ToList<string>();
                        List<object> valueList = gpr.FeatureSet.Features[i].Attributes.Values.ToList();
                        graphicsLayer.Graphics[i].Attributes.Add(keyList[j], valueList[j]);
                    } 
                }
                //在此绑定DataGrid,不然会出现异常
                MyDataGrid.GraphicsLayer = graphicsLayer;
                MyDataGrid.Visibility = Visibility.Visible;
                //绘制地形图
                if (createPlot == true)
                {
                    CreatePlot();
                    TerrainBorder.Visibility = Visibility.Visible;
                }
                featureSet.Features.Clear();
            }
            //等待过程
            BusyRectangle.Visibility = Visibility.Collapsed;
            busyIndicator.IsBusy = false;
        }

        private void _geoprocessor_Failed(object sender, TaskFailedEventArgs e)
        {
            MessageBox.Show(e.Error.ToString());
        }

以上是调用GP服务的代码,这里有个Bug。
最后的统计结果如下所示:

 

3.2.3 Web客户端绘制地形图

 这里借助的是开源的图表控件:OxyPlot。感觉绘制图表很强大,而且开源啊。

绘制地形剖面图的功能大致上的过程如下:

首先在地图上绘制一条线,然后等分这条线,例如一百份,然后得到这一百个点的像元统计值(最后的值就是海拔值,这里数据的准确度和提供的高程数据经度有关,高程数据经度越高,结果也就越准确),得到一百个点的高程数据之后,就通过OxyPlot绘图了。

具体代码:

a.OxyPlot绘图

声明一个PlotModel,PlotModel代表绘制图表的类型。

PlotModel plotModel = null;

在构造函数中初始化:

 var linearAxis1 = new LinearAxis(AxisPosition.Bottom) { IsZoomEnabled=false,Title="距离"};
            plotModel.Axes.Add(linearAxis1);
            var linearAxis2 = new LinearAxis(AxisPosition.Left) { IsZoomEnabled=false,Title="海拔"};
            plotModel.Axes.Add(linearAxis2);
            areaSeries1 = new AreaSeries
            {
                Fill=OxyColors.DarkOrange,
                DataFieldX="距离",
                DataFieldY="最高海拔",
                DataFieldX2 = "距离",
                DataFieldY2 = "最低海拔",
                Color=OxyColors.Red,
                StrokeThickness=0,
                MarkerFill=OxyColors.Transparent,
            };

b.然后绘制一条直线并构造点:

    private void CreatPoint(ESRI.ArcGIS.Client.Geometry.Polyline polyline,int count)
        {
            //默认沿直线构造一百个点
            double xStep = (polyline.Paths[0][1].X - polyline.Paths[0][0].X) / count;
            double yStep = (polyline.Paths[0][1].Y - polyline.Paths[0][0].Y) / count;
            interval = Math.Sqrt(xStep * xStep + yStep * yStep);
            //清空FeatureSet便于之后的GP服务调用
            if (featureSet.Features.Count > 0)
            {
                featureSet.Features.Clear();
            }
            for (int i = 0; i < count; i++)
            {
                MapPoint mp = new MapPoint(polyline.Paths[0][0].X + i*xStep, polyline.Paths[0][0].Y + i*yStep);
                mp.SpatialReference = map1.SpatialReference;
                Graphic gPoint = new Graphic()
                {
                    Symbol = new SimpleMarkerSymbol()
                    {
                        Color=new SolidColorBrush(Colors.Blue),
                        Size=8,
                        Style=SimpleMarkerSymbol.SimpleMarkerStyle.Circle
                    },
                    Geometry=mp,
                };
                featureSet.Features.Add(gPoint);
                graphicsLayer.Graphics.Add(gPoint);
            }
        }

c.调用GP服务统计像元值(代码如上)

d.根据统计值绘制图表,这里Graphic的MAX属性表示的即为最高海拔,对于点要素MAX和MIN值是一样的。

 private void CreatePlot()
        {
            areaSeries1.Points.Clear();
            areaSeries1.Points2.Clear();
            plotModel.Series.Clear();

            for (int i = 0; i < graphicsLayer.Graphics.Count; i++)
            {
                areaSeries1.Points.Add(new DataPoint(interval * i, Convert.ToDouble(graphicsLayer.Graphics[i].Attributes["MAX"])));
                areaSeries1.Points2.Add(new DataPoint(interval * i, 0));
            }
            plotModel.Series.Add(areaSeries1);
            areaSeries1.Title = "海拔";
            Myplot.Model = plotModel;
            createPlot = false;
        }

最后的MainPage.cs代码:

View Code
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using ESRI.ArcGIS.Client.Symbols;
using ESRI.ArcGIS.Client.Geometry;
using ESRI.ArcGIS.Client.Tasks;
using ESRI.ArcGIS.Client;
using System.Text.RegularExpressions;
using OxyPlot.Silverlight;
using OxyPlot;
namespace QueryAndStatisticDemo
{
    public partial class MainPage : UserControl
    {
        //用于查询的Task
        QueryTask queryTask = new QueryTask();
        //声明一个Draw,用于绘制查询的区域,进行空间查询
        Draw myDraw;
        //绘制的Geomotry
        ESRI.ArcGIS.Client.Geometry.Geometry drawGeometry; 
        //查询SQL字符串
        string QueryString;
        //选择查询结果中的Graphic
        Graphic selectedGraphic;
        //地理处理服务
        Geoprocessor _geoprocessor = null;
        //输入要素集
        FeatureSet featureSet = new FeatureSet();
        GraphicsLayer graphicsLayer;
        PlotModel plotModel = null;
        //Interval
        AreaSeries areaSeries1;
        double interval;
        bool createPlot = false;

        public MainPage()
        {
            InitializeComponent();
            plotModel = new PlotModel("地形剖面图");
            var linearAxis1 = new LinearAxis(AxisPosition.Bottom) { IsZoomEnabled=false,Title="距离"};
            plotModel.Axes.Add(linearAxis1);
            var linearAxis2 = new LinearAxis(AxisPosition.Left) { IsZoomEnabled=false,Title="海拔"};
            plotModel.Axes.Add(linearAxis2);
            areaSeries1 = new AreaSeries
            {
                Fill=OxyColors.DarkOrange,
                DataFieldX="距离",
                DataFieldY="最高海拔",
                DataFieldX2 = "距离",
                DataFieldY2 = "最低海拔",
                Color=OxyColors.Red,
                StrokeThickness=0,
                MarkerFill=OxyColors.Transparent,
            };
            
            graphicsLayer = map1.Layers["QueryResultLayer"] as GraphicsLayer;

            queryTask.Url = "http://qzj-pc:6080/arcgis/rest/services/Provinces_Map/HunanMap/MapServer/3";
            queryTask.AutoNormalize = true;
            //很重要,否则出现查询成功和失败交替出现的现象
            queryTask.DisableClientCaching = true;
            queryTask.ExecuteCompleted += new EventHandler<QueryEventArgs>(queryTask_ExecuteCompleted);
            queryTask.Failed += new EventHandler<TaskFailedEventArgs>(queryTask_Failed);

            _geoprocessor = new Geoprocessor("http://qzj-pc:6080/arcgis/rest/services/RasterStatisticServer/GPServer/DemStatisticsRaster");
            _geoprocessor.JobCompleted += new EventHandler<JobInfoEventArgs>(_geoprocessor_JobCompleted);
            _geoprocessor.Failed += new EventHandler<TaskFailedEventArgs>(_geoprocessor_Failed);
            _geoprocessor.GetResultDataCompleted += new EventHandler<GPParameterEventArgs>(_geoprocessor_GetResultDataCompleted);

            myDraw = new Draw(map1);
            myDraw.DrawMode = DrawMode.Polygon;
            myDraw.IsEnabled = false;
            myDraw.FillSymbol = new SimpleFillSymbol()
            {
                BorderBrush = new SolidColorBrush(Colors.Black),
                BorderThickness = 3,
                Fill = new SolidColorBrush(Colors.Red),
            };
            myDraw.LineSymbol = new LineSymbol()
            {
                Color=new SolidColorBrush(Colors.Red),
                Width=3
            };
            myDraw.DrawComplete += new EventHandler<DrawEventArgs>(myDraw_DrawComplete);

            QueryTypeCombox.ItemsSource = AttributeString.GraphicAttributesEnNameString;
        }

        private void myDraw_DrawComplete(object sender, DrawEventArgs e)
        {
            graphicsLayer.Graphics.Clear();
            drawGeometry = e.Geometry;
           
            myDraw.IsEnabled = false;

            if (drawGeometry is ESRI.ArcGIS.Client.Geometry.Polyline)
            {
                CreatPoint((ESRI.ArcGIS.Client.Geometry.Polyline)drawGeometry,100);
                BusyRectangle.Visibility = Visibility.Visible;
                busyIndicator.IsBusy = true;
                AccessGPService(featureSet);
            }
            else
            {
                 StartQueryBySpatial(e.Geometry);
            }

        }

        private void ExpressionButton_Click(object sender, RoutedEventArgs e)
        {
            string pattern = @"^[0-9]*$";

            Button button = sender as Button;
            Match m = Regex.Match(button.Content.ToString(), pattern);
            if (m.Success)
                ExpressionTextBox.Text = string.Format("{0}{1}", ExpressionTextBox.Text, button.Content);
            else
                ExpressionTextBox.Text = string.Format("{0} {1} ", ExpressionTextBox.Text, button.Content);
        }

        private void ExpressionQueryButton_Click(object sender, RoutedEventArgs e)
        {
            CreatQueryString();
            StartQueryBySQL(QueryString);
        }

        private void SpatialQueryButton_Click(object sender, RoutedEventArgs e)
        {
            ExpressionTextBox.Text = "";
            myDraw.DrawMode = DrawMode.Polygon;
            myDraw.IsEnabled = true;
        }

        private void FiledsCombox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            ComboBox comb = sender as ComboBox;
            if (comb.SelectedIndex != -1)
            {
                int index = comb.SelectedIndex;
                ExpressionTextBox.Text = string.Format("{0}{1}", ExpressionTextBox.Text, comb.SelectedItem.ToString());
            }
            comb.SelectedIndex = -1;
        }

        private void ExpressionTextBox_KeyDown(object sender, System.Windows.Input.KeyEventArgs e)
        {
            // 按了回车键就向服务端发送数据
            if (e.Key == Key.Enter)
            {
                CreatQueryString();
                StartQueryBySQL(QueryString);
            }
        }

        private void QoutButton_Click(object sender, RoutedEventArgs e)
        {
            Button button = sender as Button;
            ExpressionTextBox.Text = string.Format("{0}{1}", ExpressionTextBox.Text, button.Content);
        }

        private void NoButton_Click(object sender, RoutedEventArgs e)
        {
            Button button = sender as Button;
            ExpressionTextBox.Text = string.Format("{0} {1}", ExpressionTextBox.Text, button.Content);
        }

        private void ClearGraphicsButton_Click(object sender, RoutedEventArgs e)
        {
            graphicsLayer.Graphics.Clear();
        }

        private void GraphicsLayer_MouseLeftButtonDown(object sender, GraphicMouseButtonEventArgs e)
        {
            if (selectedGraphic != null)
            {
                selectedGraphic.UnSelect();
                selectedGraphic.Symbol = new SimpleFillSymbol()
                {
                    BorderBrush = new SolidColorBrush(Colors.Red),
                    BorderThickness = 2,
                    Fill = new SolidColorBrush(Colors.Green)
                };
            }

            e.Graphic.Select();
            e.Graphic.Symbol = new SimpleFillSymbol()
            {
                Fill=new SolidColorBrush(Colors.Red),
                BorderBrush = new SolidColorBrush(Colors.Yellow),
                BorderThickness=3
            };
            if (e.Graphic.Selected&&MyDataGrid.GraphicsLayer!=null)
                MyDataGrid.ScrollIntoView(e.Graphic, null);
            selectedGraphic = e.Graphic;
        }

        #region 查询失败几完成事件
        private void queryTask_ExecuteCompleted(object sender, QueryEventArgs e)
        {

            graphicsLayer.ClearGraphics();

            if (e.FeatureSet.Features.Count > 0)
            {
                foreach (Graphic resultFeature in e.FeatureSet.Features)
                {
                    if (drawGeometry != null)
                    {
                        //查询结果落在绘制的多边形之内
                        if (resultFeature.Geometry.Extent.XMax < drawGeometry.Extent.XMax &&
                           resultFeature.Geometry.Extent.XMin > drawGeometry.Extent.XMin &&
                           resultFeature.Geometry.Extent.YMax < drawGeometry.Extent.YMax &&
                           resultFeature.Geometry.Extent.YMin > drawGeometry.Extent.YMin)
                        {
                            resultFeature.Symbol = new SimpleFillSymbol()
                            {
                                BorderBrush = new SolidColorBrush(Colors.Red),
                                BorderThickness = 2,
                                Fill = new SolidColorBrush(Colors.Green)
                            };
                            featureSet.Features.Add(resultFeature);
                            graphicsLayer.Graphics.Add(resultFeature);
                        }
                    }
                    else
                    {
                        resultFeature.Symbol = new SimpleFillSymbol()
                        {
                            BorderBrush = new SolidColorBrush(Colors.Red),
                            BorderThickness = 2,
                            Fill = new SolidColorBrush(Colors.Green)
                        };
                        featureSet.Features.Add(resultFeature);
                        graphicsLayer.Graphics.Add(resultFeature);
                    }
                }
                if (graphicsLayer.Graphics.Count < 1)
                    MessageBox.Show("没有查询到目标要素!");
            }
            else
            {
                MessageBox.Show("没有查询到目标要素!");
            }
            drawGeometry = null;
        }

        private void queryTask_Failed(object sender, TaskFailedEventArgs e)
        {
            MessageBox.Show("Query failed: " + e.Error);
        }

        #endregion

        #region 查询自定义方法
        /// <summary>
        /// 条件查询
        /// </summary>
        /// <param name="sqlString">查询SQL语句</param>
        private void StartQueryBySQL(string sqlString)
        {
            queryTask.CancelAsync();
            if (ExpressionTextBox.Text == "")
                return;
            Query query = new Query();
            query.ReturnGeometry = true;
            query.OutFields.AddRange(new string[] { "NAME99", "ADCODE99" });
            query.Where = sqlString;
            query.OutSpatialReference = map1.SpatialReference;
            queryTask.ExecuteAsync(query);
        }
        /// <summary>
        /// 空间查询
        /// </summary>
        /// <param name="geometry">几何图形</param>
        private void StartQueryBySpatial(ESRI.ArcGIS.Client.Geometry.Geometry geometry)
        {
            queryTask.CancelAsync();
            Query query = new Query();
            query.ReturnGeometry = true;
            query.OutFields.AddRange(new string[] { "NAME99", "ADCODE99" });
            query.Geometry = geometry;
            query.SpatialRelationship = SpatialRelationship.esriSpatialRelContains;
            query.OutSpatialReference = map1.SpatialReference;
            queryTask.ExecuteAsync(query);
        }

        /// <summary>
        /// 构造查询Where条件的SQL语句
        /// </summary>
        private void CreatQueryString()
        {
            if (QueryTypeCombox.SelectedIndex == 0)
                QueryString =string.Format("NAME99 = '{0}'",ExpressionTextBox.Text);
            else if (QueryTypeCombox.SelectedIndex == 1)
                QueryString = string.Format("ADCODE99 = '{0}'",ExpressionTextBox.Text);
            else
                return;
        }
        #endregion

        # region 调用GP服务进行栅格像元统计
        private void StatisticButton_Click(object sender, RoutedEventArgs e)
        {
            if (featureSet.Features.Count <= 0)
                return;
            BusyRectangle.Visibility = Visibility.Visible;
            busyIndicator.IsBusy = true;
            AccessGPService(featureSet);
        }

        private void AccessGPService(FeatureSet featureset)
        {
            List<GPParameter> gppara = new List<GPParameter>();
            //输入GP服务的参数
            gppara.Add(new GPString("ZoneFiled", "OBJECTID"));
            gppara.Add(new GPFeatureRecordSetLayer("InputFeature", featureset));
            gppara.Add(new GPString("ZonalRaster", "hunandata"));
            _geoprocessor.SubmitJobAsync(gppara);
        }

        private void _geoprocessor_JobCompleted(object sender, JobInfoEventArgs e)
        {
            HttpWebRequest.RegisterPrefix("http://", System.Net.Browser.WebRequestCreator.ClientHttp);
            Geoprocessor gp = sender as Geoprocessor;
            //请求GP服务的结果
            gp.GetResultDataAsync(e.JobInfo.JobId, "ResultTable");
        }

        private void _geoprocessor_GetResultDataCompleted(object sender, GPParameterEventArgs e)
        {
            MyDataGrid.ItemsSource = null;
            GPRecordSet gpr = e.Parameter as GPRecordSet;
            if (gpr.FeatureSet != null)
            {
                for (int i = 0; i < gpr.FeatureSet.Features.Count; i++)
                {
                    for (int j = 2; j < gpr.FeatureSet.Features[i].Attributes.Count; j++)
                    {
                        //这里本文有个Bug,就是当FeatureDataGrid绑定到GraphicsLayer后,
                        //如果修改GrapicsLayer的属性(增加或者删除)会报错,以下代码不能通过,所以这里选择了先修改再绑定
                        List<string> keyList = gpr.FeatureSet.Features[i].Attributes.Keys.ToList<string>();
                        List<object> valueList = gpr.FeatureSet.Features[i].Attributes.Values.ToList();
                        graphicsLayer.Graphics[i].Attributes.Add(keyList[j], valueList[j]);
                    } 
                }
                //在此绑定DataGrid,不然会出现异常
                MyDataGrid.GraphicsLayer = graphicsLayer;
                MyDataGrid.Visibility = Visibility.Visible;
                //绘制地形图
                if (createPlot == true)
                {
                    CreatePlot();
                    TerrainBorder.Visibility = Visibility.Visible;
                }
                featureSet.Features.Clear();
            }
            //等待过程
            BusyRectangle.Visibility = Visibility.Collapsed;
            busyIndicator.IsBusy = false;
        }

        private void _geoprocessor_Failed(object sender, TaskFailedEventArgs e)
        {
            MessageBox.Show(e.Error.ToString());
        }

     
        #endregion

        private void terrainButton_Click(object sender, RoutedEventArgs e)
        {
            myDraw.DrawMode = DrawMode.Polyline;
            TerrainBorder.Visibility = Visibility.Collapsed;   
            myDraw.IsEnabled = true;
            createPlot = true;
        }

        private void CreatPoint(ESRI.ArcGIS.Client.Geometry.Polyline polyline,int count)
        {
            //默认沿直线构造一百个点
            double xStep = (polyline.Paths[0][1].X - polyline.Paths[0][0].X) / count;
            double yStep = (polyline.Paths[0][1].Y - polyline.Paths[0][0].Y) / count;
            interval = Math.Sqrt(xStep * xStep + yStep * yStep);
            //清空FeatureSet便于之后的GP服务调用
            if (featureSet.Features.Count > 0)
            {
                featureSet.Features.Clear();
            }
            for (int i = 0; i < count; i++)
            {
                MapPoint mp = new MapPoint(polyline.Paths[0][0].X + i*xStep, polyline.Paths[0][0].Y + i*yStep);
                mp.SpatialReference = map1.SpatialReference;
                Graphic gPoint = new Graphic()
                {
                    Symbol = new SimpleMarkerSymbol()
                    {
                        Color=new SolidColorBrush(Colors.Blue),
                        Size=8,
                        Style=SimpleMarkerSymbol.SimpleMarkerStyle.Circle
                    },
                    Geometry=mp,
                };
                featureSet.Features.Add(gPoint);
                graphicsLayer.Graphics.Add(gPoint);
            }
        }

        private void CreatePlot()
        {
            areaSeries1.Points.Clear();
            areaSeries1.Points2.Clear();
            plotModel.Series.Clear();

            for (int i = 0; i < graphicsLayer.Graphics.Count; i++)
            {
                areaSeries1.Points.Add(new DataPoint(interval * i, Convert.ToDouble(graphicsLayer.Graphics[i].Attributes["MAX"])));
                areaSeries1.Points2.Add(new DataPoint(interval * i, 0));
            }
            plotModel.Series.Add(areaSeries1);
            areaSeries1.Title = "海拔";
            Myplot.Model = plotModel;
            createPlot = false;
        }

        private void Button_MouseEnter(object sender, System.Windows.Input.MouseEventArgs e)
        {
            // TODO: Add event handler implementation here.
            BusyButton.Content = "取消";
        }

        private void Button_MouseLeave(object sender, System.Windows.Input.MouseEventArgs e)
        {
            // TODO: Add event handler implementation here.
            BusyButton.Content = "正在计算...";
        }

        private void BusyButton_Click(object sender, System.Windows.RoutedEventArgs e)
        {
            // TODO: Add event handler implementation here.
            BusyRectangle.Visibility = Visibility.Collapsed;
            busyIndicator.IsBusy = false;
        }
    }
}

最后的MainPage.xaml代码:

View Code
<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:oxy="clr-namespace:OxyPlot.Silverlight;assembly=OxyPlot.Silverlight" 
    xmlns:esri="http://schemas.esri.com/arcgis/client/2009" xmlns:toolkit="http://schemas.microsoft.com/winfx/2006/xaml/presentation/toolkit" x:Class="QueryAndStatisticDemo.MainPage"
    mc:Ignorable="d"
    d:DesignHeight="760" d:DesignWidth="960" 
    >

    <Grid x:Name="LayoutRoot">
        <Grid.Background>
            <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                <GradientStop Color="#FF65C0A5" Offset="0"/>
                <GradientStop Color="#FF1E1E1F" Offset="1"/>
                <GradientStop Color="#FF22555C" Offset="0.428"/>
                <GradientStop Color="#FF596EA1" Offset="0.681"/>
            </LinearGradientBrush>
        </Grid.Background>
        <Grid.RowDefinitions>
            <RowDefinition Height="120"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>
        <!--Map-->
        <esri:Map x:Name="map1" WrapAround="True" VerticalContentAlignment="Stretch" Grid.RowSpan="2" Margin="0">
            <esri:Map.Layers>
                <esri:LayerCollection>
                    <esri:ArcGISDynamicMapServiceLayer Url="http://qzj-pc:6080/arcgis/rest/services/Provinces_Map/HunanMap/MapServer" />
                    <esri:GraphicsLayer ID="QueryResultLayer" Opacity="0.8" MouseLeftButtonDown="GraphicsLayer_MouseLeftButtonDown"/>
                </esri:LayerCollection>
            </esri:Map.Layers>
        </esri:Map>
      
        <!--QueryBorder-->
        <Border BorderBrush="Black" BorderThickness="1" Margin="8" CornerRadius="5" Background="#7F94BCE0">
            <Grid>
                <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
                    <StackPanel VerticalAlignment="Center" HorizontalAlignment="Left" Margin="10,0,10,0">
                        <StackPanel Orientation="Horizontal" HorizontalAlignment="Left">
                            <Button x:Name="MorethanButton1" Content="1" Height="23" Width="48" Click="ExpressionButton_Click" />
                            <Button x:Name="LessthanButton2" Content="2" HorizontalAlignment="Left" Height="23" Width="48" Click="ExpressionButton_Click" />
                            <Button x:Name="EqualButton1" Content="3" Height="23" Width="43" Click="ExpressionButton_Click" />
                        </StackPanel>
                        <StackPanel Orientation="Horizontal" HorizontalAlignment="Left">
                            <Button x:Name="MoreOrEButton1" Content="4" HorizontalAlignment="Left" Height="23" Width="48" Click="ExpressionButton_Click" />
                            <Button x:Name="LessOrEqualButton1" Content="5" HorizontalAlignment="Left" Height="23" Width="48" Click="ExpressionButton_Click" />
                            <Button x:Name="LessAndMoreButton1" Content="6" Height="23" Width="43" HorizontalAlignment="Left" Click="ExpressionButton_Click" />
                        </StackPanel>
                        <StackPanel Orientation="Horizontal" HorizontalAlignment="Left">
                            <Button x:Name="LikeButton1" Content="7" HorizontalAlignment="Left" Height="23" Width="48" Click="ExpressionButton_Click" />
                            <Button x:Name="AndButton1" Content="8" HorizontalAlignment="Left" Height="23" Width="48" Click="ExpressionButton_Click" />
                            <Button x:Name="OrButton1" Content="9" Height="23" Width="43" Click="ExpressionButton_Click" />
                        </StackPanel>
                        <StackPanel Orientation="Horizontal" HorizontalAlignment="Left">
                            <Button x:Name="NotButton1" Content="0" HorizontalAlignment="Left" Height="23" Width="48" Click="ExpressionButton_Click" />
                            <Button x:Name="QoutButton" Content="'" HorizontalAlignment="Left" Height="23" Width="48" ToolTipService.ToolTip="单引号" Click="QoutButton_Click" />
                            <Button x:Name="NoButton" Content="!" Height="23" Width="43" ToolTipService.ToolTip="非运算" Click="NoButton_Click" />
                        </StackPanel>
                    </StackPanel>
                    <StackPanel VerticalAlignment="Top" HorizontalAlignment="Center" Margin="0">
                        <StackPanel Orientation="Horizontal" Margin="0,10,0,0">
                        <TextBlock  TextWrapping="Wrap" Text="查询条件:" Height="18" Margin="20,0,0,0" FontSize="14" FontWeight="Bold" Foreground="Red"/>
                            <ComboBox x:Name="QueryTypeCombox" Height="23" Width="130" SelectedIndex="0" Margin="0,0,10,0"/>
                            <TextBox x:Name="ExpressionTextBox" TextWrapping="Wrap" Height="27" Margin="0,5,0,0" Width="150" KeyDown="ExpressionTextBox_KeyDown"/>
                        </StackPanel>
                            <StackPanel Orientation="Horizontal" Margin="0,10,0,0">
                            <Button x:Name="ExpressionQueryButton" Content="条件查询" Height="30" Width="70" Margin="20,0,0,0" Click="ExpressionQueryButton_Click"/>
                            <Button x:Name="SpatialQueryButton" Content="空间查询" Height="30" Width="70" Click="SpatialQueryButton_Click" Margin="10,0,0,0" />
                            <Button Content="绘制地形图" Height="30" x:Name="terrainButton" Width="75" Margin="20,0,0,0" Click="terrainButton_Click"/>
                        </StackPanel>
                    </StackPanel>
                    <StackPanel VerticalAlignment="Center" HorizontalAlignment="Left" Margin="20,0,20,0">
                        <Button Width="135" Height="23" x:Name="StatisticButton" Content="地形统计" Margin="0,5,0,0" Click="StatisticButton_Click" />
                        <Button x:Name="ClearExpressionButton" Content="清空查询语句" Height="23" Width="135" Click="SpatialQueryButton_Click"  Margin="0,10,0,0" />
                        <Button Width="135" Height="23" x:Name="ClearGraphicsButton" Content="清空图层" Margin="0,10,0,0" Click="ClearGraphicsButton_Click" />
                      </StackPanel>
                </StackPanel>
            </Grid>
        </Border>
   
        <!--StatisticResultForm-->
        <esri:FeatureDataGrid x:Name="MyDataGrid" HorizontalAlignment="Right" Margin="0,0,20,20" VerticalAlignment="Bottom" 
                              Map="{Binding ElementName=map1}"
                              Width="400" Height="200"
                              Grid.Column="0" Grid.Row="1"  SelectionMode="Single" VerticalGridLinesBrush="#FF31D8D8" HorizontalGridLinesBrush="#FF31B1B1" RowBackground="#AA3C8A99" Visibility="Collapsed" >
            <esri:FeatureDataGrid.Effect>
                <DropShadowEffect/>
            </esri:FeatureDataGrid.Effect>
            <esri:FeatureDataGrid.Background>
                <LinearGradientBrush EndPoint="0.894,0.85" StartPoint="-0.076,-0.033">
                    <GradientStop Color="#FF56585E"/>
                    <GradientStop Color="#FF1B8D85" Offset="1"/>
                </LinearGradientBrush>
            </esri:FeatureDataGrid.Background>
        </esri:FeatureDataGrid>

        <Border BorderThickness="1" Grid.Row="1" Height="260" HorizontalAlignment="Left" Margin="20" x:Name="TerrainBorder" VerticalAlignment="Bottom" Width="400" CornerRadius="10" Visibility="Collapsed">
            <Border.Effect>
                <DropShadowEffect/>
            </Border.Effect>
            <oxy:Plot x:Name="Myplot" Foreground="#FFE9E5E5" >
                <oxy:Plot.Effect>
                    <DropShadowEffect/>
                </oxy:Plot.Effect>
                <oxy:Plot.Background>
                    <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                        <GradientStop Color="#FF0F4549" Offset="0"/>
                        <GradientStop Color="#B266AABA" Offset="1"/>
                        <GradientStop Color="#DA8F9EA1" Offset="0.471"/>
                    </LinearGradientBrush>
                </oxy:Plot.Background>
            </oxy:Plot>
        </Border>
        <Rectangle x:Name="BusyRectangle" Fill="#FF454552" Stroke="Black" Grid.RowSpan="2" Opacity="0.5" Visibility="Collapsed"/>
        <toolkit:BusyIndicator x:Name="busyIndicator" Grid.Row="1" VerticalAlignment="Center" HorizontalAlignment="Center" IsBusy="False">
            <toolkit:BusyIndicator.BusyContent>
                <Grid>
                    <Button x:Name="BusyButton" Height="23" Width="199" Content="正在计算..." MouseEnter="Button_MouseEnter" MouseLeave="Button_MouseLeave" Padding="3" Click="BusyButton_Click"/>
                </Grid>
            </toolkit:BusyIndicator.BusyContent>
        </toolkit:BusyIndicator>
    </Grid>
</UserControl>

最终的效果:

按县区名称查询双峰县,结果如下图所示:

正在统计双峰县的像元信息

统计结果如下图所示:

 

绘制一条直线

通过直线得到构造点,并进行像元统计

 

最后的统计结果,及地下剖面图,根据直线经过的地方来看,地形图是正确的。

 

在图上可以查看剖面图的数据:

空间查询,并进行统计

总结:以上的过程大致上说了一下Web端区域像元统计的过程,其中涉及到了要素查询,GP服务,Web端栅格数据作为输入数据的处理问题,OxyPlot图表控件的使用,FeatureDataGrid的数据绑定等,有些内容进行了详细的说明,有些由于时间限制就没有进行细致的说明,在此还望谅解。有什么问题可以留言反映,我一定都会逐一回复。当然程序中还有很多Bug,也没有处理,程序的结构也不是很好,代码质量也不高,希望高手勿喷,欢迎您提出宝贵的意见和分享您的解决方法。

还有需要提醒一点的是本文使用的服务都是我自己发布的服务,所以您需要自己发布程序中用到的服务。

 【源码下载

原文地址:https://www.cnblogs.com/potential/p/2938361.html