ajax GET POST 异同

javascript本身都是unicode编码的
ajax都是utf-8编码的

1 GET

var key = $("#key").val();
		var value = $("#value").val();
		var postStr = "key=" + encodeURIComponent(key) + "&value=" + encodeURIComponent(value);
		var xmlhttp_request = new XMLHttpRequest();
		xmlhttp_request.open('GET', '${ctx}/AjaxServlet?'+postStr, true);
		//xmlhttp_request.send(postStr);
		xmlhttp_request.send(null);//请求体为空
		xmlhttp_request.onreadystatechange = function() {
			if (xmlhttp_request.readyState == 4
					&& xmlhttp_request.status == 200) {
				var res = xmlhttp_request.responseText;
				alert(eval("(")+res+")");
			}
		}

2 POST

var key = $("#key").val();
		var value = $("#value").val();
		var postStr = "key=" + encodeURIComponent(key) + "&value=" + encodeURIComponent(value);
		var xmlhttp_request = new XMLHttpRequest();
		xmlhttp_request.open('POST', '${ctx}/AjaxServlet', true);
		xmlhttp_request.setRequestHeader("Content-Type",
				"application/x-www-form-urlencoded");
		xmlhttp_request.send(postStr);//传送请求体
		xmlhttp_request.onreadystatechange = function() {
			if (xmlhttp_request.readyState == 4
					&& xmlhttp_request.status == 200) {
				var res = xmlhttp_request.responseText;
				alert(eval("(")+res+")");
			}
		}

GET是一定要进行编码的
encodeURIComponent(key)
POST 貌似不需要