ASP.NET
ASP.NET

ASP.NET Google Map Markers (pushpins) and informatrion display box

I have a small project where I google map several records from my SQL database. The table has just a Latitude, Longitude and a unique record number fields. I managed to display my records on the map and show the record ID in the pushpin (label) as well in the information box when you click with the mouse over a pin (See screenshot). The problem is that the pushpin display only the first digit (I guess because of the pin size and/or the font size used by the system) of the record ID and I have about 150 records in my table. The "information box" does show the full number (See screenshot) however, if accessing the page with an iOS device, I have no idea how to brig the information box up - if there is a way. It is important for iPhone to be able to see the full Record ID in one way or another. Please be specific in you solution since I have a very limited experience in ASP.NET VB.NET. Thank you all

This is what I have in my aspx:

<%@ Page Title="" Language="vb" AutoEventWireup="false" MasterPageFile="~/Site.Mobile.Master" CodeBehind="MyMap.aspx.vb" Inherits="WebApplication1.MyMap" %>

<asp:Content ID="Content3" ContentPlaceHolderID="MainContent" runat="server">

    <!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml" > 
     <script type="text/javascript"
     src="https://maps.googleapis.com/maps/api/js?key=My_Code_Here&amp;sensor=false">
     </script>

<body onload="initialize()">
          <div id="mapArea" style="width: 500px; height: 500px;">
          </div>
 
          <asp:Literal ID="Literal1" runat="server"></asp:Literal>
</body>
</html>

</asp:Content>

Open in new window

And this is my VB code for the same page:

Imports System.Data
Imports System.Configuration
Imports System.Data.SqlClient

Public Class MapAvailableTerritories
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load


        Dim markers As String = ""
        markers = GetMarkers()
        Literal1.Text = "<script type='text/javascript'>" +
     "function initialize() {" +
     "var mapOptions = {" +
     "center: new google.maps.LatLng(35.372278, -80.633568)," +
     "zoom: 9," +
     "mapTypeId : google.maps.MapTypeId.ROADMAP" +
     "};" +
     "var myMap = new google.maps.Map(document.getElementById('mapArea'), mapOptions);" +
     markers +
     "}" +
     "</script>"


    End Sub

    Protected Function GetMarkers() As String
        Dim markers As String = ""

        Using con As New SqlConnection(ConfigurationManager.ConnectionStrings("DefaultConnection").ConnectionString)
            Dim cmd As SqlCommand = New SqlCommand("SELECT Lat, Lng, Territory FROM MyMapData", con)
            con.Open()
            Dim reader As SqlDataReader = cmd.ExecuteReader()
            Dim i As Integer = 0
            While reader.Read()
                i = i + 1
                markers = markers + "var marker" + i.ToString() + "= new google.maps.Marker({" +
               "position: new google.maps.LatLng( " + reader("Lat").ToString() + ", " +
               reader("Lng").ToString() + ")," +
               "Label:'" + reader("RecordID").ToString() + "', " +
               "map: myMap," +
               "title:'" + reader("RecordID").ToString() + "'});"


            End While
            con.Close()
        End Using
        Return markers
    End Function

End Class

Open in new window

This is the result I currently experienced (The number in the pin is also 38 as shown by the information box:

Cobra967Asked: 2016-08-12

Who is Participating?

Cobra967Author Commented: 2016-08-16

I ultimately used the code from http://www.aspsnippets.com/Articles/ASPNet-Google-Maps-V3-with-Multiple-Markers-Database-Example.aspx and it works just fine

LVL 33

Robberbaron (robr)Commented: 2016-08-14

I do something very similar but all the work is in Javascript in the aspx page.

but rather than use the Label attribute, I use the Html attribute. It can then show much more data. ( i show a list of items that apply to the pin.)

           var contentTags = '<h2><a href=\'details_projects.aspx?ProjectNo=' + Title + '\' class=\'link1\'>' + Title + '</a></h2>' + Descr;

           //surround the real text with div to style it
            var contentString = '<div id=\'content\' style=\'width:280px;\'>' + contentTags + '</div>';

            //save content into the html property

            var marker = new google.maps.Marker({
                position: latlng
                , html: contentTags
                , icon: img
            });

            google.maps.event.addListener(marker, 'click', function () {
                infowindow.close();
                infowindow.setContent(contentString);
                infowindow.open(map, marker);
            });

Open in new window

it may also be easier to create a Jscript function to do this, then call the function each time you want to add a pin.
eg i use function createMarker(latlng, Title, Descr)

the click listener should work with all webbrowsers. (dont have a i-device so cant confirm)

Cobra967Author Commented: 2016-08-14

Thank you Robberbaron! Because I am new to ASP.NET I am afraid you lost me :-) All I want is to be able to see up to 3-digits in the Pushpin (if possible - by enlarging the pushpin or reducing the font), this will assure compatibility with Windows and iOS systems which has no mouse clicking ability. Will integrating your idea work? If so, would you be so kind to help me out with the coding?

Thank you!

LVL 33

Robberbaron (robr)Commented: 2016-08-15

1. i dont think enlarging the pin is possible. I dont even know how your pins work as I had to use Icons; each icon comes as an image of that number.
2. all the browsers support 'click' but perhaps you have to add the listener.... I copied code from examples on google web site. That is where I set the width of the text that pops up.