如何從數據庫中獲取谷歌地圖用戶的位置？

我已經按照經度和緯度顯示地圖，但是我想根據可以從數據庫中檢索到的商店的位置和類型（例如藥房，醫院）來顯示地圖。如何從數據庫中獲取谷歌地圖用戶的位置？

正文內容

<script type="text/javascript" src="https://maps.googleapis.com/maps/api/js?sensor=false"></script> 
    <script type="text/javascript"> 
     var markers = [ 
     <asp:Repeater ID="rptMarkers" runat="server"> 
    <ItemTemplate> 
      { 
       "title": '<%# Eval("Name") %>', 
       "Type": '<%# Eval("Type") %>', 
       "Location": '<%# Eval("Location") %>', 
       "description": '<%# Eval("Description") %>' 
      } 
    </ItemTemplate> 
    <SeparatorTemplate> 
     , 
    </SeparatorTemplate> 
    </asp:Repeater> 
     ]; 
     window.onload = function() { 
      LoadMap(); 
     } 
     function LoadMap() { 
      var mapOptions = { 
       center: new google.maps.LatLng(markers[0].lat, markers[0].lng), 
       zoom: 8, 
       mapTypeId: google.maps.MapTypeId.ROADMAP 
      }; 
      var infoWindow = new google.maps.InfoWindow(); 
      var latlngbounds = new google.maps.LatLngBounds(); 
      var map = new google.maps.Map(document.getElementById("dvMap"), mapOptions); 
      var legend = document.getElementById("legend"); 
      legend.innerHTML = ""; 
      for (var i = 0; i < markers.length; i++) { 
       var data = markers[i] 
       var myLatlng = new google.maps.LatLng(data.lat, data.lng); 
       var marker = new google.maps.Marker({ 
        position: myLatlng, 
        map: map, 
        title: data.title, 
        icon: data.icon 
       }); 
       (function (marker, data) { 
        google.maps.event.addListener(marker, "click", function (e) { 
         infoWindow.setContent("<div style = 'width:100px;height:40px'>" + data.description + "</div>"); 
         infoWindow.open(map, marker); 
        }); 
       })(marker, data); 
       latlngbounds.extend(marker.position); 

       legend.innerHTML += "<div style = 'margin:5px'><img align = 'middle' src = '" + marker.icon + "' />&nbsp;" + marker.title + "</div>"; 
      } 
      var bounds = new google.maps.LatLngBounds(); 
      map.setCenter(latlngbounds.getCenter()); 
      map.fitBounds(latlngbounds); 
     } 

    </script> 
    <table border="0" cellpadding="0" cellspacing="0"> 
     <tr> 
      <td> 
       <div id="dvMap" style="width: 500px; height: 500px"> 
       </div> 
      </td> 
      <td id="legend" style="display:none;"> 
      </td> 
      <script async defer src="https://maps.googleapis.com/maps/api/js?key=AIzaSyAV8AiebjdcoS-Ratewz-HDkFt7XCq3zOM&libraries=places&callback=initMap"></script> 
     </tr> 
    </table> 
</body>

頁面加載

protected void Page_Load(object sender, EventArgs e) 
    { 
     if (!this.IsPostBack) 
     { 
      DataTable dt = this.GetData("select * from GetLocations"); 
      rptMarkers.DataSource = dt; 
      rptMarkers.DataBind(); 
     } 
    }

獲取數據

private DataTable GetData(string query) 
    { 
     string conString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString; 
     SqlCommand cmd = new SqlCommand(query); 
     using (SqlConnection con = new SqlConnection(conString)) 
     { 
      using (SqlDataAdapter sda = new SqlDataAdapter()) 
      { 
       cmd.Connection = con; 

       sda.SelectCommand = cmd; 
       using (DataTable dt = new DataTable()) 
       { 
        sda.Fill(dt); 
        return dt; 
       } 
      } 
     } 
    }