function getXMLHttpRequest()
{
	if(window.ActiveXObject) {
		try {
			return new ActiveXObject("Msxml2.XMLHTTP");
		} catch(e) {
			try {
				return new ActiveXObject("Microsoft.XMLHTTP");
			} catch(e1) { return null; }
		}
	} else if (window.XMLHttpRequest) {
		return new XMLHttpRequest();
	} else {
		return null;
	}
}

var httpRequest = null;

//예 : sendRequest("suggest.php", "keyword=AJAX", displayResult, 'POST');
function sendRequest(url, params, callback, method)
{
	httpRequest = getXMLHttpRequest();

	if(httpRequest == null)
	{
		alert('XMLHttpRequest 객체를 구할 수 없습니다.');
		return;
	}

	var httpMethod = method ? method : 'GET';

	if(httpMethod != 'GET' && httpMethod != 'POST')
	{
		httpMethod = 'GET';
	}

	var httpParams = (params == null || params == '') ? null : params;
	var httpUrl = url;

	if(httpMethod == 'GET' && httpParams != null)
	{
		httpUrl = httpUrl + "?" + httpParams;
	}

	httpRequest.open(httpMethod, httpUrl, true);
	httpRequest.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
	httpRequest.onreadystatechange = callback;
	httpRequest.send(httpMethod == 'POST' ? httpParams : null);
}