Developer's Guide - MapGuide Open Source - OSGeo

For example, see task_pane_redlining.php in the digitizing_features
directory in the Developer Guide samples.
Passing Coordinates
The digitizing functions in the Viewer API provide us with the digitized
coordinates on the client, but we usually need to pass them to a server side
script. This can be done by having the callback function fill in the fields of a
hidden form, and then submit the form. The form then passes the variables
to a server-side script. For example, the callback function could be:
function OnLineDigitized(line) {
// Send the Javascript variables to 'draw_line.php',
// via the hidden form defined below
document.getElementById("x0").value = line.Point(0).X;
document.getElementById("y0").value = line.Point(0).Y;
document.getElementById("x1").value = line.Point(1).X;
document.getElementById("y1").value = line.Point(1).Y;
var sessionId = "";
document.getElementById("session_id").value = sessionId;
}
document.myform.submit();
That function fills out and submits this form:
Passing Coordinates | 91