Request parameter rules |
When request parameters are duplicated with conflicting values, the response from the server may be undefined.
WMS should to be able to handle request parameters undefined in this document. In words of this standard, that is, this parameter is unnecessary to WMS.
Parameter names shall not be case sensitive, but parameter values shall be. In this International Standard, parameter names are typically shown in uppercase for typographical clarity, not as a requirement.
Parameters in a request may be specified in any order.
When request parameters are duplicated with conflicting values, the response from the server may be not predefined. This International Standard does not mandate which of the duplicated values sent by the client are to be used by the server.
A WMS shall be prepared to encounter additional request parameters that are not part of this International Standard. In terms of producing results per this International Standard, a WMS shall not require such parameters.
Parameters consisting of lists (for example, BBOX, LAYERS and STYLES in WMS GetMap) shall use the comma (",") as the separator between items in the list. If a list item value includes a space or comma, it shall be escaped using the URL encoding rules
In some lists, individual entries may be empty, and shall be represented by the empty string ("").Thus, two successive commas indicate an empty item, as does a leading comma or a trailing comma. An empty list ("") shall be interpreted either as a list containing no items or as a list containing a single empty item, depending on context.