var browser = navigator.appName;


function getNewXMLHttpRequest() {
  var obj;
    try {
      // For Internet Explorer.
      obj = new ActiveXObject("Microsoft.XMLHTTP");
      }
    catch(e) {
      try {
        // Gecko-based browsers, Safari, and Opera.
        obj = new XMLHttpRequest();
      }
      catch (e) {
        // Browser supports Javascript but not XMLHttpRequest.
        obj = false;
      }
    }
    return obj;
}

function write_comment(article_id) {
	var writer_name = document.getElementById("username").value;
	var website = document.getElementById("website").value;
	var comment = document.getElementById("comment").value;
	comment = comment.replace(/\&/g, "[amp]");
	comment = comment.replace(/\+/g, "[plus]");
	xmlhttp = getNewXMLHttpRequest();		
	xmlhttp.open("POST", "/system/comment/comment_interface.php?action=insert_comment",true);
	xmlhttp.onreadystatechange=function() {
		if (xmlhttp.readyState==4) {

			if(xmlhttp.responseText!="") {
				window.location="http://"+xmlhttp.responseText;
			}
		}
		
	}
	xmlhttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded'); 
	xmlhttp.send("writer_name="+writer_name+"&comment="+comment+"&article_id="+article_id+"&website="+website);	
	var writer_name = document.getElementById("username").value="";
	var comment = document.getElementById("comment").value="";
}