var jsonResult = NSArray()

do {

jsonResult = try JSONSerialization.jsonObject(with: data, options:JSONSerialization.ReadingOptions.allowFragments) as! NSArray

} catch let error as NSError {

print(error)

}

var jsonElement = NSDictionary()

let locations = NSMutableArray()

for i in 0 ..< jsonResult.count

{

jsonElement = jsonResult[i] as! NSDictionary

let location = LocationModel()

//以下通过可选绑定确保JsonElement值都不为空

if let evIdL = jsonElement["id"] as? String,

let evUserNameL = jsonElement["username"] as? String,

let evNotikindL = jsonElement["notikind"] as? String,

let evLatiL = jsonElement["lati"] as? String,

let evLongiL = jsonElement["longi"] as? String,

let evLocatL = jsonElement["locat"] as? String,

let evTimedateL = jsonElement["timedate"] as? String,

let evDistanceL = jsonElement["distance"] as? String

{

location.evId = evIdL

location.evUsername = evUserNameL

location.evNotikind = evNotikindL

location.evLati = evLatiL

location.evLongi = evLongiL

location.evLocat = evDistanceL

location.evTimedate = evTimedateL

location.evDisatnce = evDistanceL

location.evLocat = evLocatL

// 显示位置的代码

let latiCon = (location.evLati as NSString).doubleValue

let longiCon = (location.evLongi as NSString).doubleValue

let annotations = locations.map { location -> MKAnnotation in

let annotation = MKPointAnnotation()

annotation.title = evNotikindL

annotation.coordinate = CLLocationCoordinate2D(latitude:latiCon, longitude: longiCon)

return annotation

}

self.map.showAnnotations(annotations, animated: true)

self.map.addAnnotations(annotations)

}

locations.add(location)

}

DispatchQueue.main.async(execute: { () -> Void in

self.itemsDownloaded(items: locations)

})

}