openlayers+geojson
投影, projection: new OpenLayers.Projection(“EPSG:4326”)//900913
要么不要，要么是4326，不然绘制的json对象不会显示。
最后一句 map.zoomToMaxExtent();
必须加，不然地图不能缩放。
如果用gmap第三版，用IE，会出现vector图层和底图拖动不一致的情况，第二版不会。
tmd，openlayers调googlemap，总是会出这样那样的问题。
/**
* 使用了openlayers、xuhy.VT.js,
*/
var xuhy = xuhy ? xuhy : {};
xuhy.Map = xuhy.Map ? xuhy.Map
: {
Map: function() {
var _this = this;
var gmap,styles,map, draw, modify, snap, split, vectors;
_this.Fix = function(number, num) {
with (Math) return round(number.valueOf() * pow(10, num)) / pow(10, num);
};
_this.Initialize = function() {
try {
OpenLayers.DOTS_PER_INCH = 72; //90.71428571428572;//25.4 / 0.28
OpenLayers.Util.onImageLoadErrorColor = ‘transparent’;
OpenLayers.IMAGE_RELOAD_ATTEMPTS = 3;
OpenLayers.INCHES_PER_UNIT[“公里”] = OpenLayers.INCHES_PER_UNIT[“km”];
OpenLayers.INCHES_PER_UNIT[“米”] = OpenLayers.INCHES_PER_UNIT[“m”];
OpenLayers.INCHES_PER_UNIT[“尺”] = OpenLayers.INCHES_PER_UNIT.m / 3.0;
styles = new OpenLayers.StyleMap({
“default”: new OpenLayers.Style(null, {
rules: [
new OpenLayers.Rule({
symbolizer: {
“Point”: {
pointRadius: 5,
graphicName: “square”,
fillColor: “white”,
fillOpacity: 0.25,
strokeWidth: 1,
strokeOpacity: 1,
strokeColor: “#3333aa”
},
“Line”: {
strokeWidth: 3,
strokeOpacity: 1,
strokeColor: “#6666aa”
},
“Polygon”: {
strokeWidth: 1,
strokeOpacity: 1,
fillColor: “#9999aa”,
strokeColor: “#6666aa”
}
}
})
]
}),
“select”: new OpenLayers.Style(null, {
rules: [
new OpenLayers.Rule({
symbolizer: {
“Point”: {
pointRadius: 5,
graphicName: “square”,
fillColor: “white”,
fillOpacity: 0.25,
strokeWidth: 2,
strokeOpacity: 1,
strokeColor: “#0000ff”
},
“Line”: {
strokeWidth: 3,
strokeOpacity: 1,
strokeColor: “#0000ff”
},
“Polygon”: {
strokeWidth: 2,
strokeOpacity: 1,
fillColor: “#0000ff”,
strokeColor: “#0000ff”
}
}
})
]
}),
“temporary”: new OpenLayers.Style(null, {
rules: [
new OpenLayers.Rule({
symbolizer: {
“Point”: {
graphicName: “square”,
pointRadius: 5,
fillColor: “white”,
fillOpacity: 0.25,
strokeWidth: 2,
strokeColor: “#0000ff”
},
“Line”: {
strokeWidth: 3,
strokeOpacity: 1,
strokeColor: “#0000ff”
},
“Polygon”: {
strokeWidth: 2,
strokeOpacity: 1,
strokeColor: “#0000ff”,
fillColor: “#0000ff”
}
}
})
]
})
});
} catch (e) {
throw new Error(“Initialize->:\n” + e.name + “:” + e.message)
}
};
_this.MousePositionFormatOutput = function(lonLat) {
var templon = “东经:”
var templat = “北纬:”
if (lonLat.lon < 0) {
templon = “西经:”;
}
if (lonLat.lat < 0) {
templat = “南纬:”
}
templon += _this.Fix(Math.abs(lonLat.lon), 4);
templat += _this.Fix(Math.abs(lonLat.lat), 4);
return templon + “,” + templat;
};
//加载google地图
_this.loadMap = function() {
try {
var options = {
controls: [
new OpenLayers.Control.Navigation(),
new OpenLayers.Control.MousePosition({formatOutput: _this.MousePositionFormatOutput}),
new OpenLayers.Control.LayerSwitcher()
, new OpenLayers.Control.PanZoomBar()//
, new OpenLayers.Control.OverviewMap({ maximized: true })
, new OpenLayers.Control.ScaleLine({ topOutUnits: “公里”, topInUnits: “米”, bottomOutUnits: “米”, bottomInUnits: “尺” })
]
//,allOverlays: true
, projection: new OpenLayers.Projection(“EPSG:4326”)//900913
, displayProjection: new OpenLayers.Projection(“EPSG:4326”)
, units: “m”
, maxResolution: 156543.034
, maxExtent: new OpenLayers.Bounds(-20037508.34, -20037508.34, 20037508.34, 20037508.34)//20037508.34
};
map = new OpenLayers.Map(‘map’, options);
gmap = new OpenLayers.Layer.Google(
xuhy.Map.MapName_Road, // the default
{numZoomLevels: 20
, isBaseLayer: true }
);
map.addLayer(gmap);
// create three vector layers
vectors = new OpenLayers.Layer.Vector(“Lines”, {
strategies: [new OpenLayers.Strategy.Fixed()],
protocol: new OpenLayers.Protocol.HTTP({
url: “../data/test.json”,
format: new OpenLayers.Format.GeoJSON()
}),
styleMap: styles
// ,maxExtent: new OpenLayers.Bounds(1549471.9221, 6403610.94, 1550001.32545, 6404015.8)
});
map.addLayer(vectors);
map.zoomToMaxExtent();
} catch (e) {
throw new Error(“loadMap->:\n” + e.name + “:” + e.message)
}
};
}
}
// 文档初始化
$(document).ready(function() {
try {
//
document.body.clientWidth;// ==> BODY对象宽度
var newheight = document.documentElement.clientHeight – 2; // ==> BODY对象高度
document.getElementById(“map”).style.height = newheight + ‘px’;
//alert(“create map”);
var MapInstance = new xuhy.Map.Map();
MapInstance.Initialize();
MapInstance.loadMap();
} catch (e) {
alert(“初始化出错：\n” + e.name + “:” + e.message)
}
});
/*
// configure the snapping agent
snap = new OpenLayers.Control.Snapping({ layer: vectors });
map.addControl(snap);
snap.activate();
// configure split agent
split = new OpenLayers.Control.Split({
layer: vectors,
source: vectors,
tolerance: 0.0001,
eventListeners: {
aftersplit: function(event) {
flashFeatures(event.features);
}
}
});
map.addControl(split);
split.activate();
// add some editing tools to a panel
var panel = new OpenLayers.Control.Panel({
displayClass: “olControlEditingToolbar”
});
draw = new OpenLayers.Control.DrawFeature(
vectors, OpenLayers.Handler.Path,
{ displayClass: “olControlDrawFeaturePoint”, title: “Draw Features” }
);
modify = new OpenLayers.Control.ModifyFeature(
vectors, { displayClass: “olControlModifyFeature”, title: “Modify Features” }
);
panel.addControls([
new OpenLayers.Control.Navigation({ title: “Navigate” }),
draw, modify
]);
map.addControl(panel);
map.addControl(new OpenLayers.Control.MousePosition());
*/
转载自：https://blog.csdn.net/xuhaiyan8825/article/details/6957863
