arcgis api for javascript 坐标转换

var lonlat={x:114.514864,y:38.04232};
var mercator={x:12747736.346966475,y:4585405.935084799};

//经纬度转墨卡托
function lonlat2mercator(lonlat){
var mercator={x:0,y:0};
var x = lonlat.x *20037508.34/180;
var y = Math.log(Math.tan((90+lonlat.y)*Math.PI/360))/(Math.PI/180);
y = y *20037508.34/180;
mercator.x = x;
mercator.y = y;
return mercator ;
}

//墨卡托转经纬度
function mercator2lonlat(mercator){
var lonlat={x:0,y:0};
var x = mercator.x/20037508.34*180;
var y = mercator.y/20037508.34*180;
y= 180/Math.PI*(2*Math.atan(Math.exp(y*Math.PI/180))-Math.PI/2);
lonlat.x = x;
lonlat.y = y;
return lonlat;

}

//墨卡托转经纬度定位

var dx = sGeometry.x / 20037508.34 * 180;
var dy = sGeometry.y / 20037508.34 * 180;
var M_PI = Math.PI;
dy = 180 / M_PI * (2 * Math.atan(Math.exp(dy * M_PI / 180)) - M_PI / 2);
//地理坐标x为:122.10626710683903
//地理坐标y为:37.48735577057014
// x=dx;
// y=dy;
var cPoint=new esri.geometry.Point();
cPoint.x=dx;
cPoint.y=dy;
console.log(cPoint);
map.centerAt(cPoint);