将JavaScript变量发送到要与表单一起提交的另一页

Question

Let me explain.... I am trying to have the user confirm their location on one page using Google Maps v3 API. I want to save and send the position variable (the latitude and longitude) of the user to the next page to be submitted with a form the user fills out. In the end the form is submitted to a database.

I believe the variable I am wanting to save is the following:

var pos = new google.maps.LatLng(position.coords.latitude,position.coords.longitude);

The script is in the Site.Master in the heading.

Would creating a form and sending it to the next page be the easiest way to accomplish this?

Google Maps Page:

<%@ Page Title="Roadside Assistance: Location" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="RoadsideLoc.aspx.cs"     Inherits="Final_Project.RoadsideLoc" %>
<asp:Content ID="Content1" ContentPlaceHolderID="HeaderContent" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<div style="text-align:center">
    <h1>Is this the location of your vehicle?</h1>

</div>

<div id="map-canvas" style="height:350px">

</div>

<div data-role="controlgroup" data-type="horizontal" style="text-align:center" runat="server">
    <a href="Roadside.aspx?" data-role="button">Yes</a>
    <a href="RoadsideLocNO.aspx" data-role="button">No</a>

</div>


</asp:Content>

Answer 1

You could use localStorage or sessionStorage to store lat/lng and then recreate a LatLng object when you need it.

Alternatively you can use cookies to store you data on client side.

Answer 2

You can accomplish this by applying several methods.

1. After the user confirms their location, do something like

    var lat = position.coords.latitude, long = position.coords.longitude; window.location = "sitemaster2.aspx?latitude=" + lat + "&longitude=" + long; 

   This way, you will be able to access this coordinates in the second page and attach them to the desired form.

2. Right before leaving the page append the current URL the coordinates. You can do that with history.pushState . When you get to the form, search the history for your entry and get the coordinates out of the URL.

3. Set a cookie with the coords and get them back on the second page.

4. Asynchronously load an asp file which sets a session holding the coords. Then get them by checking the sessions.

5. Put the coords in a hidden POST form and make the user actually submit the form when pressing the confirm button.

Or don't change the pages at all. You can just have both pages in one. Split the body in two and alternatively show each part as a step to submitting the necessary data.