jQuery $.post execute success instead of error if connection to server is lost

I'm using this code to connect to the server via jQuery

var jqxhr = $.post('@Url.Action("../CheckMessage")',  { 'MessageId': MessageId }, 
    function (data, s) {
        alert ('This is executed on success only - data: ' + data + 's: ' + s);
    }
)
.error(function(XMLHttpRequ开发者_C百科est, textStatus, errorThrown) { alert("error"})

If I create a new exception in the server .error method is correctly executed, but if I take the server down, then success method is executed. How can I check if the connection to the server was lost?

---

Ajax recall the cached data for subsequent request if you do not sepecify cache as false in the ajax setting. Try this cache:false using $.ajax.

$.ajax({
     url:  '@Url.Action("../CheckMessage")',
     data: { 'MessageId': MessageId }, 
     cache: false,
     success: function (data, s) {
        alert ('This is executed on success only - data: ' + data + 's: ' + s);
     },
     error: function(XMLHttpRequest, textStatus, errorThrown) { 
       alert("error");
     }
});

.