ol2加载ArcGis发布的wfs

来源：互联网发布：linux中的dd命令编辑：程序博客网时间：2024/05/21 22:58

通用接入WFS

Wfs服务主要功能

：属性查询包含图像查询。支持各种条件和查询数据库一样。

也支持删除、修改、增加，支持空间查询和比较。

使用Acrgis发布wfs服务；方法自行百度；

获取wfs数据的代码：

通过与配合能够得到查询条件；然后拼凑到整个查询参数当中去就行。

从上面我们也能看出来，请求其实就是ajax的post请求。只是对于 wfs 来说查询参数需要是GML格式的（就是一种xml，只不过里面的节点名称都是指定的有一定的规则，不然不能被arcgis识别）；

获取过来的数据可以通过直接转化为feature对象，然后通过layer加载就可以显示了。

wfs查询参数的格式：

下面的就是查询参数的格式，可以看出来就是个xml，格式化后就是：

Filter部分条件也就是构造的查询条件。

关于跨域

请上面的请求我们能看出来：传入的参数中有个参数：

这个参数其实就是服务器的路径，由于请求是跨域的，所以使用了代理服务器，在后台获取的，所以就要把原始路径传递过去。

Ol中使用代理服务需要在js中加一行代码：

这个官方有定义。

下面附上 ashx的完整跨域代码：其实代理服务就是设置了一个后台的获取功能。没有啥东西。以前以为代理是什么呢，草。

<%@WebHandler Language="C#"Class="Handler" %>

using System;

usingSystem.Collections.Generic;

using System.Web;

using System.Net;

using System.IO;

public classHandler : IHttpHandler {

public void ProcessRequest (HttpContext context) {

if (string.IsNullOrEmpty(context.Request["URL"]))return;

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(context.Request["URL"]);

request.UserAgent = context.Request.UserAgent;

request.ContentType =context.Request.ContentType;

request.Method =context.Request.HttpMethod;

byte[] trans = new byte[10240];

int offset = 0;

int offcnt = 0;

if (request.Method.ToUpper() =="POST")

{

Stream nstream =request.GetRequestStream();

while (offset <context.Request.ContentLength)

{

offcnt = context.Request.InputStream.Read(trans,offset, 10240);

if (offcnt > 0)

{

nstream.Write(trans, 0, offcnt);

offset +=offcnt;

}

nstream.Close();

}

HttpWebResponse response = (HttpWebResponse)request.GetResponse();

//Encoding enc =Encoding.GetEncoding(65001);

context.Response.ContentType = response.ContentType;

StreamReader loResponseStream =new StreamReader(response.GetResponseStream());

string lcHtml =loResponseStream.ReadToEnd();

context.Response.Write(lcHtml);

response.Close();

loResponseStream.Close();

}

public bool IsReusable {

get {

return false;

}

完整代码：

<!DOCTYPEhtml PUBLIC "-//W3C//DTD XHTML 1.0Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<htmlxmlns="http://www.w3.org/1999/xhtml">

<head>

<scriptsrc="../Lib/jquery/jquery-1.8.3.all.js"></script>

<scriptsrc="../OpenLayers2.13/OpenLayers.js"></script>

<scriptsrc="../OpenLayers2.13/lib/deprecated.js"></script>

<style>

html,body

{

height:100%;

overflow:hidden;

width:100%;

}

#map

{

height:500px;

width:1000px;

border:2pxred solid;

}

</style>

<scripttype="text/javascript">

var map, drawLayer; var drawLayer;

function init() {

//添加代理

OpenLayers.ProxyHost = 'Handler.ashx?URL=';

var options = {

controls: [],

projection: "EPSG:4326"

};

map = new OpenLayers.Map('map', options);

var tiled = new OpenLayers.Layer.WMS(

"province","http://ltserver:6080/arcgis/services/MyMapService/MapServer/WmsServer",

{

"LAYERS":'0',

"STYLES":'',

format: 'image/png'

{

buffer: 0,

isBaseLayer:true

}

);

map.addLayer(tiled);

drawLayer = new OpenLayers.Layer.Vector("drawLayer");

map.addLayer(drawLayer);

map.addControl(new OpenLayers.Control.PanZoomBar({

position: new OpenLayers.Pixel(2, 15)

}));

map.addControl(new OpenLayers.Control.Navigation());

map.addControl(new OpenLayers.Control.LayerSwitcher());

map.setCenter([117,36],6);

GetGeoJson();

}

function GetGeoJson(layerName) {

var filter = new OpenLayers.Filter.Logical({

type:OpenLayers.Filter.Logical.AND,

filters: [

new OpenLayers.Filter.Comparison({//比较操作符

type:OpenLayers.Filter.Comparison.LIKE,

property: "所在市",

value: "温州市"

}),

new OpenLayers.Filter.Comparison({//比较操作符

type: OpenLayers.Filter.Comparison.LIKE,

property: "所在市",

value: "温州市"

})

]

});

var filter_1_0 = new OpenLayers.Format.Filter.v1_0_0();

var xml = new OpenLayers.Format.XML();

var xmlPara = '<?xml version="1.0"encoding="utf-8" ?>'

+ "<wfs:GetFeatureservice='WFS' version='1.0.0' outputFormat='GML2' "

+ "xmlns:wfs='http://www.opengis.net/wfs'"

+ "xmlns:gml='http://www.opengis.net/gml' "

+ "xmlns:ogc='http://www.opengis.net/ogc'"

+ "xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'"

+ "xsi:schemaLocation='http://www.opengis.net/wfs http://schemas.opengis.net/wfs/1.0.0/wfs.xsd'> "

+ "<wfs:QuerytypeName='ProtectDev:功能区方案'srsName='EPSG:4326' >"

+ "<wfs:PropertyName>ProtectDev:所在市</wfs:PropertyName>"

+xml.write(filter_1_0.write(filter)) //添加查询条件，报错，目前是获取全部数据

+ "</wfs:Query>"

+ "</wfs:GetFeature>";

var request = OpenLayers.Request.POST({

url: "http://ltserver:6080/arcgis/services/ProtectDev/MapServer/WFSServer?",

data: xmlPara,

callback: function (e) {

var gmlParse =new OpenLayers.Format.GML();

var features =gmlParse.read(e.responseText);

drawLayer.addFeatures(features);

}

});

}

</script>

</head>

<bodyonload="init()">

<divid="map"></div>

</body>

</html>

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