JS经纬度距离计算代码分享

 GetDistance:function(lat1, lng1, lat2, lng2, len_type = 2, decimal = 2) 
 { 
 var radLat1 = lat1 * Math.PI / 180.0; //PI()圆周率 
 var radLat2 = lat2 * Math.PI / 180.0; 
 var a = radLat1 - radLat2; 
 var b = (lng1 * Math.PI / 180.0) - (lng2 * Math.PI / 180.0); 
 var s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a/2),2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b/2),2))); 
 s = s * 6378.137; 
 s = Math.round(s * 1000); 
 if (len_type --> 1) 
 { 
 s /= 1000; 
 } 
 return Math.round(s, decimal); 
},