linestring.js

用来在地图上做操作GIS,在地图上做标记

/* Copyright (c) 2006-2007 MetaCarta, Inc., published under the BSD license.
 * See http://svn.openlayers.org/trunk/openlayers/release-license.txt 
 * for the full text of the license. */

/**
 * @requires OpenLayers/Geometry/Curve.js
 * 
 * Class: OpenLayers.Geometry.LineString
 * A LineString is a Curve which, once two points have been added to it, can 
 * never be less than two points long.
 * 
 * Inherits from:
 *  - <OpenLayers.Geometry.Curve>
 */
OpenLayers.Geometry.LineString = OpenLayers.Class(OpenLayers.Geometry.Curve, {

    /**
     * Constructor: OpenLayers.Geometry.LineString
     * Create a new LineString geometry
     *
     * Parameters:
     * points - {Array(<OpenLayers.Geometry.Point>)} An array of points used to
     *          generate the linestring
     *
     */
    initialize: function(points) {
        OpenLayers.Geometry.Curve.prototype.initialize.apply(this, arguments);        
    },

    /**
     * APIMethod: removeComponent
     * Only allows removal of a point if there are three or more points in 
     * the linestring. (otherwise the result would be just a single point)
     *
     * Parameters: 
     * point - {<OpenLayers.Geometry.Point>} The point to be removed
     */
    removeComponent: function(point) {
        if ( this.components && (this.components.length > 2)) {
            OpenLayers.Geometry.Collection.prototype.removeComponent.apply(this, 
                                                                  arguments);
        }
    },

    CLASS_NAME: "OpenLayers.Geometry.LineString"
});