（五）ArcGIS JS FindTask 按属性查询地图信息

超、凢脫俗 2021-09-14 16:40 385阅读 0赞

### 前言 ###

我们在使用ArcGIS JS API时，会遇到在文本框中输入名称，查询该要素，实现要素的查找功能。

### 准备 ###

*  在本地部署ArcGIS JS API/调用在线的API
    
     *  [本地部署ArcGIS JS API][ArcGIS JS API]
 *  发布好的动态地图服务
    
     *  [http://blog.csdn.net/idomyway/article/details/79232011][http_blog.csdn.net_idomyway_article_details_79232011]

### 思路 ###

*  HTML页文本框接收查询名称
 *  点击事件触发API中的findTask查询
    
     *  实例化findTask参数FindParameters并设置
     *  实例化FindTask参数并调用execute函数
 *  将获得的要素定位高亮显示
    
     *  在回调函数中新建图形符号
     *  设置获得findTask查询得到geometry
     *  获得中心点坐标并进行定位
 *  在table面板中展示信息
    
     *  利用数组获得查询信息
     *  在table中展示信息

### 代码实现 ###

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Hello World</title>
        <link rel="stylesheet" type="text/css" href="http://localhost:8080/arcgis_js_api/library/3.20/3.20/dijit/themes/tundra/tundra.css"/>
        <link rel="stylesheet" type="text/css" href="http://localhost:8080/arcgis_js_api/library/3.20/3.20/esri/css/esri.css" />
        <script type="text/javascript" src="http://localhost:8080/arcgis_js_api/library/3.20/3.20/init.js"></script>
        <style>
            *{
                padding: 0px;
                margin:0px;
            }
            table{
                margin-top: 10px;
                border-collapse: collapse;
                overflow-y: scroll;
            }
            th,td{
                padding: 0px;
                border:1px solid #000;
            }
        </style>
    </head>
    <body class="tundra">
        <div id="mapDiv" style="width:calc(100% - 2px); height:800px; border:1px solid #000;"></div>
        Name:<input id="searchInput" type="text">
        <input id="btn" type="button" value="查询">
        <table >
            <thead>
                <tr>
                    <th width="100px">名称</th>
                    <th width="100px">类型</th>
                    <th width="100px">面积</th>
                </tr>
            </thead>
            <tbody id="infoBody">
            </tbody>
        </table>
        <script>
        require(["esri/map",
                "dojo/query",
                "dojo/dom",
                "dojo/on",
                "esri/layers/ArcGISDynamicMapServiceLayer",
                "esri/tasks/FindTask",
                "esri/tasks/FindParameters",
                "esri/symbols/SimpleMarkerSymbol",
                "esri/symbols/SimpleLineSymbol",
                "esri/symbols/SimpleFillSymbol",
                "esri/geometry/Point",
                "esri/Color",
                "esri/graphic",
                "dojo/domReady!"],
            function(Map,query,dom,on,ArcGISDynamicMapServiceLayer,FindTask,FindParameters,SimpleMarkerSymbol,
                     SimpleLineSymbol,SimpleFillSymbol,Point,Color,Graphic){
                var nameArr=[];//用于存储查询地点名称
                var shapeArr=[];//用于存储查询shape
                var areaArr=[];//用于存储面积
                var map = new Map("mapDiv");
                var layer=new ArcGISDynamicMapServiceLayer("http://localhost:6080/arcgis/rest/services/firstTest/firstService/MapServer");
                map.addLayer(layer);
                query("#btn").on("click",function(){
                    var name=dom.byId("searchInput").value;//获得输入框的值
                    map.graphics.clear();//清空graphics
                    //实例化查询参数
                    var findParams = new FindParameters();
                    findParams.returnGeometry = true;
                    findParams.layerIds = [0,2];//对地级城市和省记性查询
                    findParams.searchFields = ["name"];//匹配图层中的name属性
                    findParams.searchText = name;
                    //实例化查询对象
                    var findTask = new FindTask("http://localhost:6080/arcgis/rest/services/firstTest/firstService/MapServer");
                    //进行查询
                    findTask.execute(findParams,showFindResult)
                });
                function showFindResult(queryResult)
                {
                    //初始化信息暂存数组
                    nameArr=[];
                    shapeArr=[];
                    areaArr=[];
                    if (queryResult.length === 0) {
                        alert("查询无结果");
                        return;
                    }
                    for (var i = 0; i < queryResult.length; i++) {
                        nameArr[i]=queryResult[i].feature.attributes.NAME;
                        shapeArr[i]=queryResult[i].feature.attributes.Shape;
                        areaArr[i]=queryResult[i].feature.attributes.AREA;
                        //定义高亮图形的符号
    
                        var pointSymbol = new SimpleMarkerSymbol(//定义点符号
                            SimpleMarkerSymbol.STYLE_CIRCLE, 10,
                            new SimpleLineSymbol(SimpleLineSymbol.STYLE_SOLID,
                                new Color([255,0,0]), 1),
                            new Color([255,0,0]));
                        var outline= new SimpleLineSymbol(SimpleLineSymbol.STYLE_DASHDOT,new Color([255, 0, 0]), 1); //定义面的边界线符号
                        var PolygonSymbol = new SimpleFillSymbol(SimpleFillSymbol.STYLE_SOLID, outline,new Color([0, 255, 0, 1])); //定义面符号
    
                        var graphic ={}; //创建graphic
                        var locationPoint ={};//创建定位点
                        var geometry = queryResult[i].feature.geometry;//获得该图形的形状
                        if(geometry.type ==="polygon"){
                            graphic = new Graphic(geometry, PolygonSymbol);
                            locationPoint=geometry.getCentroid();
                        }
                        else if(geometry.type ==="point"){
                            graphic = new Graphic(geometry, pointSymbol);
                            locationPoint=geometry;
                        }
                        //将图形添加到map中
                        map.graphics.add(graphic);
                        map.centerAndZoom(locationPoint,1);
                    }
                    var html="";
                    for(var i=0;i<nameArr.length;i++){
                        html+="<tr>" +
                                " <td >"+nameArr[i]+"</td>" +
                                "<td >"+shapeArr[i]+"</td>" +
                                "<td >"+areaArr[i]+"</td>"+
                            "</tr>";
                    }
                    dom.byId("infoBody").innerHTML =html;
                }
            })
    </script>
    </body>
    </html>

### 运行结果 ###

*  查询前

![这里写图片描述][SouthEast]

*  城市查询

![这里写图片描述][SouthEast 1]

*  省查询

![这里写图片描述][SouthEast 2]

### 注意问题 ###

*  发布图层服务结构

![这里写图片描述][SouthEast 3]

[ArcGIS JS API]: http://blog.csdn.net/idomyway/article/details/78648907
[http_blog.csdn.net_idomyway_article_details_79232011]: http://blog.csdn.net/idomyway/article/details/79232011
[SouthEast]: /images/20210726/b8ab13da9e82445f884b4d1df80d7ec3.png
[SouthEast 1]: /images/20210726/5c99f0629ace4e01b49cc5fd83f0888f.png
[SouthEast 2]: /images/20210726/0b4044681a12458a9d83ab9532cc51e2.png
[SouthEast 3]: /images/20210726/28e3a91af21641f08c2202dac0a6cf28.png