Since you didn't specify which language you wanted to use - here is an example using JavaScript:
var serverUrl = Xrm.Page.context.getClientUrl();
var oDataSelect = serverUrl + "/XRMServices/2011/OrganizationData.svc/EmailSet(guid'" + emailId + "')?$select=DirectionCode";
var req = new XMLHttpRequest();
req.open("GET", oDataSelect, false);
req.setRequestHeader("Accept", "application/json");
req.setRequestHeader("Content-Type", "application/json;charset=utf-8");
req.onreadystatechange = function () {
if (req.readyState === 4) {
if (req.status === 200) {
var retrieved = JSON.parse(req.responseText).d;
alert(retrieved.DirectionCode);
}
}
};
req.send();
Jason Lattimer
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