在地图上画多边形Ajax查询

最新推荐文章于 2022-08-18 19:38:47 发布

原创最新推荐文章于 2022-08-18 19:38:47 发布 · 1.2k 阅读

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文章标签：

#ajax #attributes #string #function #null #button

本文介绍了一种在地图上绘制多边形并进行Ajax查询的方法。通过客户端脚本实现多边形绘制，服务器端脚本则负责处理查询请求并返回查询结果。此方案适用于地理信息系统（GIS）应用中的空间查询。

在地图上画多边形Ajax查询

1. 前台标签及脚本：

<input id="Button1" type="button" value="画多边形查询" onclick="spatialExtentSearch();" /></div> <div id="queryTableContainer"></div> <mce:script type="text/javascript"></mce:script>

2.服务器端脚本：

using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Text; namespace BoxSearchApp { public partial class _Default : System.Web.UI.Page, System.Web.UI.ICallbackEventHandler { protected String returnValue; protected void Page_Load(object sender, EventArgs e) { String cbReference = Page.ClientScript.GetCallbackEventReference(this, "arg", "ReceiveServerData", "context"); String callbackScript; callbackScript = "function CallServer(arg, context)" + "{ " + cbReference + ";}"; Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "CallServer", callbackScript, true); } public void RaiseCallbackEvent(String eventArgument) { string[] envelope = eventArgument.ToString().Split(new Char[] { ',' }); double xmin = Convert.ToDouble(envelope[0]); double ymin = Convert.ToDouble(envelope[1]); double xmax = Convert.ToDouble(envelope[2]); double ymax = Convert.ToDouble(envelope[3]); StringBuilder sb = new StringBuilder(); sb.Append("<table border='1px'>"); foreach (ESRI.ArcGIS.ADF.Web.DataSources.IGISFunctionality gisFunctionality in Map1.GetFunctionalities()) { ESRI.ArcGIS.ADF.Web.DataSources.IGISResource gisResource = gisFunctionality.Resource; bool supported = gisResource.SupportsFunctionality(typeof(ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality)); if (supported) { ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality queryFunctionality = (ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality)gisResource.CreateFunctionality (typeof(ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality), null); string[] layerIDs = null; string[] layerNames = null; queryFunctionality.GetQueryableLayers(null, out layerIDs, out layerNames); ESRI.ArcGIS.ADF.Web.Geometry.Envelope adfEnvelope = new ESRI.ArcGIS.ADF.Web.Geometry.Envelope(xmin, ymin, xmax, ymax); ESRI.ArcGIS.ADF.Web.SpatialFilter spatialFilter = new ESRI.ArcGIS.ADF.Web.SpatialFilter(); spatialFilter.Geometry = adfEnvelope; spatialFilter.ReturnADFGeometries = true; spatialFilter.MaxRecords = 10; System.Data.DataTable queryResultsDataTable = queryFunctionality.Query(gisFunctionality.Name, layerIDs[0], spatialFilter); queryResultsDataTable.TableName = gisResource.Name + "_" + layerNames[0]; for (int i = 0; i < queryResultsDataTable.Rows.Count; i++) { sb.Append("<tr>"); for (int j = 0; j < queryResultsDataTable.Columns.Count; j++) { sb.Append("<td>"); sb.Append(queryResultsDataTable.Rows[i][j].ToString()); sb.Append("</td>"); } sb.Append("</tr>"); } sb.Append("</table>"); } } returnValue = sb.ToString(); } public String GetCallbackResult() { return returnValue; } } }

3.最后结果如下：

在地图上画多边形Ajax查询