我正在使用此方法来查询计算的距离是否小于限制。然后它将执行此查询方法传回 request.html 页面。或者，如果只计算的距离小于限制，那么还有其他方法来执行查询，然后它会将查询传回 request.html 页面。
this.getRequest = this.angFire.list('request', {
query: {
orderByChild: 'reqdetails',
startAt: 'reqdetails'
}
})
我收到此错误：
我的 openMapPage()方法：
openMapPage()
{
// GETTING THE CURRENT USER ADDRESS FOR LATITUDE AND LONGTITUDE
var uid = firebase.auth().currentUser.uid;
var ref = firebase.database().ref("request/" + uid);
ref.once("value").then((snapshot) => { // <------ Here!
var a = snapshot.exists(); // true
var c = snapshot.hasChild("reqdetails"); // true
var d = snapshot.child('reqdetails').exists();
var requestsKey = snapshot.key;
var requestsValue = snapshot.val();
ref.once('value', (request) => {
var currentUserAddress = request.val().regdetails.address;
var geocoder = new google.maps.Geocoder();
geocoder.geocode( { 'address': currentUserAddress}, function(results, status) {
if (status == google.maps.GeocoderStatus.OK) {
var latitude = results[0].geometry.location.lat();
var longitude = results[0].geometry.location.lng();
this.latlng = new google.maps.LatLng(latitude, longitude);
//console.log("HAHAH current user");
//var meterLimit = this.latlng;
//var userAddress = new LatLng(currentUserAddress);
//console.log("SURESH IS COOL");
}
});
});
//END OF CURRENT USER
});
// GETTING THE ALL USER ADDRESS FOR LATITUDE AND LONGTITUDE
var ref1 = firebase.database().ref("request");
ref1.once("value").then((snapshot1) => { // <------ Here!
var a = snapshot1.exists(); // true
var c = snapshot1.hasChild("reqdetails"); // true
var d = snapshot1.child('reqdetails').exists();
var requestsKey = snapshot1.key;
var requestsValue = snapshot1.val();
snapshot1.forEach((childSnapshot) => { // <------ And here!
var requestKey = childSnapshot.key;
var requestValue = childSnapshot.val();
var reqdetails = requestValue.reqdetails;
var AllUserAddress = requestValue.regdetails.address;
var geocoder1 = new google.maps.Geocoder();
geocoder1.geocode( { 'address': AllUserAddress}, function(results, status) {
var limit = 10;
if (status == google.maps.GeocoderStatus.OK) {
var latitude1 = results[0].geometry.location.lat();
var longitude1 = results[0].geometry.location.lng();
this.latlng1 = new google.maps.LatLng(latitude1, longitude1);
//var userAddress = new LatLng(currentUserAddress);
//console.log(latlng1);
var dist: number = parseInt((google.maps.geometry.spherical.computeDistanceBetween(this.latlng,this.latlng1) / 1000).toFixed(2));
if(dist < limit)
{
console.log(dist);
console.log(AllUserAddress);
this.getRequest = this.angFire.list('request', {
query: {
orderByChild: 'reqdetails',
startAt: 'reqdetails'
}
})
}
}
});
});
});
}
我的 request.html 页面
我的构造函数：
constructor(public navCtrl: NavController, public navParams: NavParams, private angFire: AngularFireDatabase,private af: AngularFireDatabase,
private afAuth: AngularFireAuth) {
}
2 回答
查看构造函数，
angFire应存在于您的类中。这意味着唯一的解释是this不是指你的班级。查看引发错误的代码，它被封装在一个回调函数中，您不使用 typescript 符号。如果你声明你的回调函数 linq-like，你可能会得到你的类的正确引用：
不要将
this关键字直接用于代码。尝试使用该方法的这一行在任何地方使用此行