$.extend({
     webService: function(params){
        var data = "{}";
        if(params.data){
            data = params.data;
        }
        $.ajax({
           type: "POST",
           url: params.url,
           data: data,
           contentType: "application/json; charset=utf-8",
           dataType: "json",
           success: params.success,
           error: params.error
        });
     } 
});

$.fn.enable = function() {
     return this.each(function() {
          $(this).removeAttr('disabled');
     });
}

$.fn.disable = function() {
     return this.each(function() {
          $(this).attr("disabled", "true");
     });
}

$.fn.block = function() {
     return this.each(function() {
          $(this).css("display","block");
     });
}

$.fn.displayNone = function() {
     return this.each(function() {
          $(this).css("display","none");
     });
}