Javascript Json, eval json, jQuery json การใช้ json ร่วมกับ Javascript

$(function(){

//#### ::[อันนี้เป็นชุดข้อมูล json ที่สมมุติขึ้นมานะครับ]
var _strJson = "{\"query\":{\"count\":9,\"created\":\"2012-11-16T03:25:46Z\",\"lang\":\"en-US\",\"results\":{\"rate\":[ " +
	       "{\"id\":\"USDTHB\",\"Name\":\"USD to THB\",\"Rate\":\"30.70\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"30.725\",\"Bid\":\"30.675\"}," +
	       "{\"id\":\"USDNOK\",\"Name\":\"USD to NOK\",\"Rate\":\"5.7617\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"5.763\",\"Bid\":\"5.7605\"}," +
	      "{\"id\":\"USDEUR\",\"Name\":\"USD to EUR\",\"Rate\":\"0.7829\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"0.783\",\"Bid\":\"0.7828\"}," +
	      "{\"id\":\"USDAUD\",\"Name\":\"USD to AUD\",\"Rate\":\"0.9675\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"0.9675\",\"Bid\":\"0.9674\"}," +
	     "{\"id\":\"USDGBP\",\"Name\":\"USD to GBP\",\"Rate\":\"0.6305\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"0.6306\",\"Bid\":\"0.6304\"}," +
	     "{\"id\":\"USDDKK\",\"Name\":\"USD to DKK\",\"Rate\":\"5.84\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"5.8403\",\"Bid\":\"5.8397\"}," +
	     "{\"id\":\"USDSEK\",\"Name\":\"USD to SEK\",\"Rate\":\"6.7659\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"6.7674\",\"Bid\":\"6.7644\"}," +
	     "{\"id\":\"USDSGD\",\"Name\":\"USD to SGD\",\"Rate\":\"1.2272\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"1.2275\",\"Bid\":\"1.227\"}," +
	     "{\"id\":\"USDAED\",\"Name\":\"USD to AED\",\"Rate\":\"3.6731\",\"Date\":\"11/16/2012\",\"Time\":\"10:25pm\",\"Ask\":\"3.6736\",\"Bid\":\"3.6726\"}" +
        "]}}}";
		
               try
	{
	
                   //#### ใช้ eval ในการทำให้ ข้อมูลที่อยู่ในรูปแบบ json ให้เป็น object
                   var _json = eval("(" + _strJson + ")");


	  //#### ::[ทำแบบวนลูป for]
	  for(var index = 0;index < _json["query"]["results"]["rate"].length;index++)
	  {
	     var item = _json["query"]["results"]["rate"][index];
	     alert("Loop " + index + "\n\nid\t::>\t" + item["id"] + "\n" +
	     	  "Name\t::>\t" + item["Name"] + "\n" + 
	                  "Rate\t::>\t" + item["Rate"] + "\n" + 
		  "Date\t::>\t" + item["Date"] + "\n" + 
		  "Time\t::>\t" + item["Time"] + "\n" + 
		  "Ask\t::>\t" + item["Ask"] + "\n" + 
		  "Bid\t::>\t" + item["Bid"] + "\n"
	           );
                   }

			
	  /*
                  //### ถ้าต้องการใช้แบบนี้ให้เอา Comment ออกนะครับ
                  //#### ::[ทำแบบวนลูป Foreach]
	 for(var _index in _json["query"]["results"]["rate"])
	 {
	    var _tr = $("<tr></tr>");
	    var item = _json["query"]["results"]["rate"][_index];
	    alert("Loop " + _index + "\n\nid\t::>\t" + item["id"] + "\n" +
	            "Name\t::>\t" + item["Name"] + "\n" + 
	            "Rate\t::>\t" + item["Rate"] + "\n" + 
	            "Date\t::>\t" + item["Date"] + "\n" + 
	            "Time\t::>\t" + item["Time"] + "\n" + 
	            "Ask\t::>\t" + item["Ask"] + "\n" + 
	            "Bid\t::>\t" + item["Bid"] + "\n"
	    );
			}*/
               }catch(e)
               {
                  alert(e.message);
               }
		
});