[OpenLayers-Users] Unsetting request parameters

[Jon Blower]

Hi all,

I've created a very simple Layer type for Web Map Servers using version
1.3.0.  This is very similar to the existing WMS layer type, which is for
WMS1.1.1.  My code for the WMS1.3 layer looks like this:

OpenLayers.Layer.WMS1_3 = Class.create();
OpenLayers.Layer.WMS1_3.prototype = 
  Object.extend( new OpenLayers.Layer.WMS(), {

    DEFAULT_PARAMS: { service: "WMS",
                      version: "1.3.0",
                      request: "GetMap",
                      styles: "",
                      exceptions: "INIMAGE",
                      format: "image/png",
                      crs: "CRS:84"
                     },
                     
    CLASS_NAME: "OpenLayers.Layer.WMS1_3"
});

This works fine, but there's a minor bug.  Note that the coordinate
reference systems is now specified by the "CRS" parameter, not the "SRS"
parameter that is used in WMS1.1.1.  The URLs that are generated for the
call to the GetMap function look like this:

&SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&STYLES=&EXCEPTIONS=INIMAGE
&FORMAT=image/png&CRS=CRS:84&SRS=EPSG:4326&BBOX=...

Note that the "CRS" and "SRS" parameters both appear in the URL.  This
doesn't really matter because the "SRS" parameter is ignored by WMS1.3
servers.  However, for the sake of neatness, is there a way of "unsetting"
the SRS parameter so that it doesn't appear in the URL?  I tried setting
"SRS: null" in the DEFAULT_PARAMS section of the above code but that didn't
seem to work.

Thanks in advance,
Jon


-------------------------------------------------------------- 
Dr Jon Blower              Tel: +44 118 378 5213 (direct line) 
Technical Director         Tel: +44 118 378 8741 (ESSC) 
Reading e-Science Centre   Fax: +44 118 378 6413 
ESSC                       Email: jdb at mail.nerc-essc.ac.uk 
University of Reading 
3 Earley Gate 
Reading RG6 6AL, UK 
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