c# - Request.Params to String gives incomplete data -

don't know if character encoding issue

i made post request asp.net page, send xml, in order value variable made this

string selectionxml = httputility.urldecode(request.params["selection"]); 

this example of xml

<?xml version="1.0" encoding="utf-8"?> <featureset> <layer id="0adcf012"> <class id="mytable"> <id>aaaaaaamvea=</id> <id>aaaaaac+5ea=</id> </class> </layer> </featureset> 

the problem is, when perform above sentence xml

<?xml version="1.0" encoding="utf-8"?> <featureset> <layer id="0adcf012"> <class id="mytable"> <id>aaaaaaamvea=</id> <id>aaaaaac 5ea=</id> </class> </layer> </featureset> 

i.e. second id tag (aaaaaac 5ea=) appears without plus sign (+) unlike original xml (aaaaaac+5ea=)

how can fix issue?

edit: add more code, asp.net page (using mapguide library)

<%@ page language="c#" debug="true" validaterequest="false"%> <%@ import namespace="system" %> <%@ import namespace="system.collections.specialized" %> <%@ import namespace="system.io" %> <%@ import namespace="osgeo.mapguide" %>  <!-- #include file="common.aspx" --> <%      response.charset = "utf-8";     string sessionid;     string mapname;     string locale;     int target=0;     int popup=0;     string selectedlayer;     mgselection selection = null;     sessionid = request.params["session"];     mapname = request.params["mapname"];     locale = request.params["locale"];     target = int.parse(request.params["tgt"]);     popup = int.parse(request.params["popup"]);     selectedlayer = request.params["layertarget"];      bool todos = false;     try     {        // initialize web extensions , connect server using       // web extensions session identifier stored in php session state.        //mapguideapi.mginitializewebtier (constants.webconfigpath);       initializewebtier();       mguserinformation userinfo = new mguserinformation(sessionid);       mgsiteconnection siteconnection = new mgsiteconnection();       siteconnection.open(userinfo);        mgmap map = new mgmap(siteconnection);       map.open(mapname);        // ----------------------------------------------------------       // use following code ajax or dwf viewers       // requires passing selection data via http post        mgreadonlylayercollection layers = null;       **string selectionxml = httputility.urldecode(request.params["selection"]);**       if (selectionxml!= null)       {         selection = new mgselection(map, selectionxml);         layers = selection.getlayers();       }        .......... 

how can fix issue?

why using httputility.urldecode? it's xml, not url! long you're using post request don't need httputility.urldecode.