Ajax请求到控制器C＃

How do to get a simple text and display it in an alert, via ajax with ExtJS 4 from a controller in c #.

example:

//Server
public JsonResult simpleData(){
 var text = "simple data";
 return Json(text, JsonRequestBehavior.AllowGet);
}

your code

public JsonResult simpleData(){
 var text = "simple data";
 return Json(text, JsonRequestBehavior.AllowGet);
}

must be :

public JsonResult simpleData(){
 var text = "simple data";
 return Json(new {data = text}, JsonRequestBehavior.AllowGet);
}

for ajax in EXTJS 4 (maybe I'm wrong), read here: Extjs4 - Ajax Request : Url generation