WKT与ArcGIS的feature互转
1、封装WKTUtil.js
var WKTUtil = function(options){
this.initialize(options);
}
WKTUtil.prototype = {
/**
* Constructor: OpenLayers.Format.WKT
* Create a new parser for WKT
*
* Parameters:
* options - {Object} An optional object whose properties will be set on
* this instance
*
* Returns:
* {<OpenLayers.Format.WKT>} A new WKT parser.
*/
initialize: function(options) {
this.regExes = {
'typeStr': /^\s*(\w+)\s*\(\s*(.*)\s*\)\s*$/,
'spaces': /\s+/,
'parenComma': /\)\s*,\s*\(/,
'doubleParenComma': /\)\s*\)\s*,\s*\(\s*\(/, // can't use {2} here
'trimParens': /^\s*\(?(.*?)\)?\s*$/
};
for(var i in options){
this[i] = options[i];
}
},
/**
* APIMethod: read
* Deserialize a WKT string and return a vector feature or an
* array of vector features. Supports WKT for POINT, MULTIPOINT,
* LINESTRING, MULTILINESTRING, POLYGON, MULTIPOLYGON, and
* GEOMETRYCOLLECTION.
*
* Parameters:
* wkt - {String} A WKT string
*
* Returns:
* {<OpenLayers.Feature.Vector>|Array} A feature or array of features for
* GEOMETRYCOLLECTION WKT.
*/
read: function(wkt) {
var features, type, str;
wkt = wkt.replace(/[\n\r]/g, " ");
var matches = this.regExes.typeStr.exec(wkt);
if(matches) {
type = matches[1].toLowerCase();
str = matches[2];
if(this.parse[type]) {
features = this.parse[type].apply(this, [str]);
//console.log(features);
}
}
return features;
},
/**
* Method: extractGeometry
* Entry point to construct the WKT for a single Geometry object.
*
* Parameters:
* geometry - {<OpenLayers.Geometry.Geometry>}
*
* Returns:
* {String} A WKT string of representing the geometry
*/
extractGeometry: function(geometry) {
var type = geometry.CLASS_NAME.split('.')[2].toLowerCase();
if (!this.extract[type]) {
return null;
}
if (this.internalProjection && this.externalProjection) {
geometry = geometry.clone();
geometry.transform(this.internalProjection, this.externalProjection);
}
var wktType = type == 'collection' ? 'GEOMETRYCOLLECTION' : type.toUpperCase();
var data = wktType + '(' + this.extract[type].apply(this, [geometry]) + ')';
return data;
},
trim: function(str){
return str.replace(/^\s\s*/, '').replace(/\s\s*$/, '');
},
/**
* Object with properties corresponding to the geometry types.
* Property values are functions that do the actual parsing.
*/
parse: {
/**
* Return point feature given a point WKT fragment.
* @param {String} str A WKT fragment representing the point
* @returns {OpenLayers.Feature.Vector} A point feature
* @private
*/
'point': function(str) {
var coords = this.trim(str).split(this.regExes.spaces);
coords[0]=Number(coords[0]);
coords[1]=Number(coords[1]);
return coords;//new esri.geometry.Point(coords[0], coords[1]);
},
/**
* Return a multipoint feature given a multipoint WKT fragment.
* @param {String} str A WKT fragment representing the multipoint
* @returns {OpenLayers.Feature.Vector} A multipoint feature
* @private
*/
'multipoint': function(str) {
var point;
var points = this.trim(str).split(',');
var components = [];
for(var i=0, len=points.length; i<len; ++i) {
point = points[i].replace(this.regExes.trimParens, '$1');
components.push(this.parse.point.apply(this, [point]).geometry);
}
return new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.MultiPoint(components)
);
},
/**
* Return a linestring feature given a linestring WKT fragment.
* @param {String} str A WKT fragment representing the linestring
* @returns {OpenLayers.Feature.Vector} A linestring feature
* @private
*/
'linestring': function(str) {
var points = this.trim(str).split(',');
var components = [];
for(var i=0, len=points.length; i<len; ++i) {
components.push(this.parse.point.apply(this, [points[i]]));
}
return components//new esri.geometry.Polyline(components);
},
/**
* Return a multilinestring feature given a multilinestring WKT fragment.
* @param {String} str A WKT fragment representing the multilinestring
* @returns {OpenLayers.Feature.Vector} A multilinestring feature
* @private
*/
'multilinestring': function(str) {
var line;
var lines = OpenLayers.String.trim(str).split(this.regExes.parenComma);
var components = [];
for(var i=0, len=lines.length; i<len; ++i) {
line = lines[i].replace(this.regExes.trimParens, '$1');
components.push(this.parse.linestring.apply(this, [line]).geometry);
}
return new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.MultiLineString(components)
);
},
/**
* Return a polygon feature given a polygon WKT fragment.
* @param {String} str A WKT fragment representing the polygon
* @returns {OpenLayers.Feature.Vector} A polygon feature
* @private
*/
'polygon': function(str) {
var ring, linestring, linearring;
var rings = this.trim(str).split(this.regExes.parenComma);
var components = [];
for(var i=0, len=rings.length; i<len; ++i) {
ring = rings[i].replace(this.regExes.trimParens, '$1');
linestring = this.parse.linestring.apply(this, [ring]);
components.push(linestring);
}
return components;
},
/**
* Return a multilinestring feature given a multilinestring WKT fragment.
* @param {String} str A WKT fragment representing the multilinestring
* @returns {OpenLayers.Feature.Vector} A multilinestring feature
* @private
*/
'multipolygon': function(str) {
str=str.substring(1,str.length-1);
var ring, linestring, linearring;
var rings = this.trim(str).split(this.regExes.parenComma);
var components = [];
for(var i=0, len=rings.length; i<len; ++i) {
ring = rings[i].replace(this.regExes.trimParens, '$1');
linestring = this.parse.linestring.apply(this, [ring]);
components.push(linestring);
}
return components;
},
}
}
2、WKT转ArcGIS
WktToPolygon:function(wkt){
var wktUtil = new WKTUtil();
var points = wktUtil.read(wkt);
var json = {
rings: points,
spatialReference: {"wkid":4490}
}
var polygon = new esri.geometry.Polygon(json);
return polygon;
},
3、ArcGIS转WKT
PolygontoWKT:function(geometry){
var wkt=[];
var rings=geometry.rings;
for(var i=0;i<rings.length;i++){
var ring=rings[i];
for(var j=0;j<ring.length;j++){
var p=ring[j];
wkt.push(p.join(" "));
}
}
return "POLYGON (("+wkt.join(',')+"))";
},