GetFeatureInfo

Brent Pedersen indirectly gave me the idea to start the User Recipes after he had offer up his solution to the email list.

Starting with findLayerClick(), which takes in an event and then packages up an URL to send to the WMS server using GetFeatureInfo instead of GetMap.

/*
 * An event occurred so now drill down the layers to get the info
 */
function findLayerClick(event) {

    layerlist = "here,there,everywhere";

    mouseLoc = map.getLonLatFromPixel(event.xy);

    var url = prox.getFullRequestString({
                REQUEST: "GetFeatureInfo",
                EXCEPTIONS: "application/vnd.ogc.se_xml",
                BBOX: map.getExtent().toBBOX(),
                X: event.xy.x,
                Y: event.xy.y,
                INFO_FORMAT: 'text/plain',
                QUERY_LAYERS: layerlist,
                FEATURE_COUNT: 1,
                WIDTH: map.size.w,
                HEIGHT: map.size.h},
                "http://server.org/cgi-bin/wmsmap?");

    OpenLayers.loadURL(url, '', this, setHTML);

    Event.stop(e);
}

NOTE:

prox is a layer defined elsewhere
mouseLoc is used later in setHTML()

findLayerClick is triggered by a mouseclick and defined in init() like;

map.events.register('click',findLayerClick);

Now for the callback setHTML, that was referenced in the OpenLayers.loadURL() above, loads in plain text
(a xml version below)

/*
 * Get the Ajax response and pop up a info bubble
 */
function setHTML(response) {
    if (response.responseText.indexOf('no results') == -1) {
        var cat="Unknown", src="Unknown", leg="Unknown", linkinfo="";
        var lines = response.responseText.split('\n');
        for (lcv = 0; lcv < (lines.length); lcv++) {
            var vals = lines[lcv].replace(/^\s*/,'').replace(/\s*$/,'').replace(/ = /,"=").replace(/'/g,'').split('=');
            if (vals[1] == "") {
                vals[1] = "Unknown";
            }
            if (vals[0].indexOf('CATEGORY') != -1 ) {
                cat = vals[1];
            } else if (vals[0].indexOf('SOURCE') != -1 ) {
                src = vals[1];
            } else if (vals[0].indexOf('LEGEND') != -1 ) {
                leg = vals[1];
            } else if (vals[0].indexOf('DATAITEM') != -1 ) {
                linkinfo = vals[1];
            }
        }
        var popup_info = "<font size=2><b>" + cat +
                        "<br>Description:</b> " + leg +
                        "<br><a href='" + linkinfo + "' target='_blank'>More Info</a>" +
                        "<br><font size=1>Source: " + src +
                        "</font></font>";
        if (popup != null) {
            popup.destroy();
            popup = null;
        }
        popup = new OpenLayers.Popup.AnchoredBubble("SDVegetationInfo",
                                        mouseLoc,
                                        new OpenLayers.Size(250,120),
                                        popup_info,
                                        null,
                                        true);
        popup.setBackgroundColor("#bcd2ee");
//      popup.setOpacity(.7);
        map.addPopup(popup);
        popup.events.register("click", map, popupDestroy);
    }
}

xml version of setHTML

function setHTML(response) {
    var popup_info = "";

var doce = response.responseXML.documentElement;
var PCode = doce.getElementsByTagName('PCode')[0].firstChild.data;
var SCode = doce.getElementsByTagName('SCode')[0].firstChild.data;
        popup_info = "<font size=2><b>Project: </b>" + PCode +
                "<br>System Code: " + SCode + "</font>";

        if (popup != null) {
            popup.destroy();
            popup = null;
        }
        popup = new OpenLayers.Popup.AnchoredBubble("SDVegetationInfo",
                                        mouseLoc,
                                        new OpenLayers.Size(250,120),
                                        popup_info,
                                        null,
                                        true);
        popup.setBackgroundColor("#bcd2ee");
//      popup.setOpacity(.7);
        map.addPopup(popup);
        popup.events.register("click", map, popupDestroy);
    }

}

NOTE: popup is global var

And lastly the function popupDestroy

/*
 * Destroy popup and stop event
 */
function popupDestroy(e) {
    popup.destroy();
    popup = null;
    OpenLayers.Util.safeStopPropagation(e);
}

submitted by bwoodall