I've tried all of the classic ie tricks to get my webpage to rerender the changes that have been made in the dom but nothing has worked. I've already tried
element.className = element.className;
as well as accessing some part of the dom I changed but that doesn't work either.
Here's my code. Onload the body calls queryDB and in the html there's a paragraph with the id "plants". So far this code only works correctly on firefox 3 and chrome.
var timeout = 5000; //get new plants every 5 seconds
function queryDB() {
responseDoc = getXMLFrom("ajax/getallplants.php");
paragraph = document.getElementById("plants");
table = document.createElement("table");
table.setAttribute("class", "viewTable");
//clean up the last query
cleanUpLastResult(paragraph);
//loop through the responseDoc and dynamically add plants
if(plantsFound(responseDoc)) {
for(i = 0; i < responseDoc.documentElement.childNodes.length; i++) {
currentChild = responseDoc.documentElement.childNodes[i];
row = document.createElement("tr");
//old way of printing where the whole sci name and common name was just text
/*paragraph.appendChild(document.createTextNode(responseDoc.documentElement.childNodes[i].firstChild.nodeValue));
paragraph.appendChild(document.createElement("br"));*/
//newer way of printing where the common name is bolded
/*paragraph.appendChild(document.createTextNode(currentChild.firstChild.nodeValue + " "));
commonName = document.createElement("b");
commonName.appendChild(document.createTextNode(currentChild.getAttribute("commonname")));
paragraph.appendChild(commonName);
paragraph.appendChild(document.createElement("br"));*/
//newest way of printing that prints to a table
col1 = document.createElement("td");
col1.setAttribute("class", "viewTable");
col1.appendChild(document.createTextNode(currentChild.firstChild.nodeValue));
col2 = document.createElement("td");
col2.setAttribute("class", "viewTable");
col2Bold = document.createElement("b");
col2Bold.appendChild(document.createTextNode(currentChild.getAttribute("commonname")));
col2.appendChild(col2Bold);
row.appendChild(col1);
row.appendChild(col2);
table.appendChild(row);
}
paragraph.appendChild(table);
paragraph.className = paragraph.className;
paragraph.firstChild.className = paragraph.firstChild.className;
}
else {
paragraph.appendChild(document.createTextNode("no plants currently entered"));
}
//re-add the callback
setTimeout(queryDB, timeout);
}
function plantsFound(responseDoc) {
if(responseDoc.documentElement == null) {
return false;
}
else {
if(responseDoc.documentElement.firstChild.nodeType == 3) {
//text node so no children
return false;
}
else {
return true;
}
}
}
function cleanUpLastResult(paragraph) {
//old way of cleaning up where everything was only a childnode of the paragraph
/*while(paragraph.childNodes.length >= 1) {
paragraph.removeChild(paragraph.firstChild);
}*/
/* The three possible cases:
* 1 first execution time so paragraph has no child
* 2 nth execution time but nothing was found in db so only a textnode
* 3 nth execution and there's a whole table to clean up
*/
if(paragraph.firstChild == null) {
//nothing there so nothing to delete
}
else if(paragraph.firstChild.nodeValue != null) {
//no table printed, just remove that text node
paragraph.removeChild(paragraph.firstChild);
}
else {
//delete the whole table
table = paragraph.firstChild;
//remove each row
while(table.childNodes.length >= 1) {
//remove the two columns in it and their stuff
row = table.firstChild;
col1 = row.firstChild;
col2 = row.lastChild;
//remove column1 and it's text node
col1.removeChild(col1.firstChild);
row.removeChild(row.firstChild);
//remove column2, it's bold node and its text node
col2.firstChild.removeChild(col2.firstChild.firstChild);
col2.removeChild(col2.firstChild);
row.removeChild(row.firstChild);
table.removeChild(row);
}
//finally delete the table
paragraph.removeChild(paragraph.firstChild);
}
}
function getXMLFrom(url) {
if(window.XMLHttpRequest) {
//regular browser
xmlhttp = new XMLHttpRequest();
}
else {
//ie6
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.open("GET", url, false);
xmlhttp.send();
responseDoc = xmlhttp.responseDoc;
if(responseDoc == null) {
if(window.XMLHttpRequest && (typeof DOMParser != "undefined")) {
//firefox
var parser = new DOMParser();
开发者_StackOverflow中文版 responseDoc = parser.parseFromString(xmlhttp.responseText, "text/xml");
}
else {
//ie6 or ie7
var doc = new ActiveXObject("Microsoft.XMLDOM");
doc.async = true;
doc.loadXML(xmlhttp.responseText);
responseDoc = doc;
}
if(responseDoc == null) {
alert("error in parser xml from: " + url);
}
return responseDoc;
}
}
I've also tested the responseDoc and I know I am getting a correct response from getallplants.php which generates an xml representations of various plants. Any ideas on how to fix this? Also, for various reasons I can't use JQuery for this.
edit I have a quasi-good solution that I found on another SO thread. If I add document.write(document.all[0].innerHTML); to queryDB after I set the table I made to a child of the paragraph. The only problem is that if I do this the page won't refresh every 5 minutes. So if the database it changed this page has to be refreshed which kind of defeats the purpose of having javascript asynchroniously get info from the database.
I had a similar issue, a few weeks ago, and adding a class to the body element made the trick. The added class can be removed just after.
精彩评论