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For loop variable undefined in Javascript

I'm working on implementing a system where elements can be dragged and dropped to create flowcharts. My Issue is with saving the flowchart so that it could be reloaded when needed. For now I've created a method that saves all the previous data of the element onto the final array that holds only elements that are dropped on the container. But I'm getting a Trivial Error as Undefined variable on the debugging interface. Hence I'm not getting the intended output and the alert messages that I included are not being printed when the condition is met.
Code in Context
function saveFlowchart()
{
var nodes = [];
var matches = [];
var searchEles = document.getElementById("container").children;
for(var i = 0; i < searchEles.length; i++)
{
matches.push(searchEles[i]);
var idOfEl = searchEles[i].id;
if(searchEles[i].id !=null || searchEles[i].id !="")
{
var $element = $("#" + searchEles[i].id);
var dropElem = $("#" + searchEles[i].id).attr('class');
var position = $element.position();
position.bottom = position.top + $element.height();
position.right = position.left + $element.width();
alert("class:"+dropElem+"\nTop position: " + position.top + "\nLeft position: " + position.left + "\nBottom position: " + position.bottom + "\nRight position: " + position.right);
finalArray[idOfEl-1][0]= idOfEl;
finalArray[idOfEl-1][1]= dropElem;
var elId = parseInt(idOfEl);
if (dropElem == "stream ui-draggable")
{
for(var count=0;count<100;count++)
{
alert("One loop opened with count="+count);
if(createdImportStreamArray[count][0]==elId)
{
finalArray[elId-1][2]= createdImportStreamArray[count][1]; //Selected Stream from Predefined Streams
finalArray[elId-1][3]= createdImportStreamArray[count][2]; //asName
alert("createdImportStreamArray[count][0]==elId");
}
else if(createdExportStreamArray[count][0]==elId)
{
finalArray[elId-1][2]= createdExportStreamArray[count][1]; //Selected Stream from Predefined Streams
finalArray[elId-1][3]= createdExportStreamArray[count][2]; //asName
}
else if(createdDefinedStreamArray[count][0]==elId)
{
finalArray[elId-1][2]= createdDefinedStreamArray[count][1]; //Stream Name
finalArray[elId-1][3]= createdDefinedStreamArray[count][4]; //Number of Attributes
finalArray[elId-1][4]=[];
for(var f=0;f<createdDefinedStreamArray[r][4];f++)
{
finalArray[elId-1][4][f][0]=createdDefinedStreamArray[count][2][f][0]; //Attribute Name
finalArray[elId-1][4][f][1]=createdDefinedStreamArray[count][2][f][1]; // Attribute Type
}
}
alert("One loop closed with count="+count);
}
alert("Loop ended with count="+count);
}
else if (dropElem == "wstream ui-draggable")
{
ElementType="wstream";
}
// else if conditions...
alert(finalArray);
}
}
//Code to output the connection details in a json format
//The following is not affected by the above mentioned error
$(".node").each(function (idx, elem) {
var $elem = $(elem);
var endpoints = jsPlumb.getEndpoints($elem.attr('id'));
console.log('endpoints of '+$elem.attr('id'));
console.log(endpoints);
nodes.push({
blockId: $elem.attr('id'),
nodetype: $elem.attr('data-nodetype'),
positionX: parseInt($elem.css("left"), 10),
positionY: parseInt($elem.css("top"), 10)
});
});
var connections = [];
$.each(jsPlumb.getConnections(), function (idx, connection) {
connections.push({
connectionId: connection.id,
pageSourceId: connection.sourceId,
pageTargetId: connection.targetId
});
});
var flowChart = {};
flowChart.nodes = nodes;
flowChart.connections = connections;
flowChart.numberOfElements = numberOfElements;
var flowChartJson = JSON.stringify(flowChart);
//console.log(flowChartJson);
$('#jsonOutput').val(flowChartJson);
}
Debugging Interface
According to this the count variable in the for loop is undefined. I've tried taking the first statement var count=0 outside the loop declaration part and defining it in the very beginning of the method. But that simply checks for count=0 against the conditions and doesn't increment at all.
Any help in this regard will be highly appreciated as I've been working on this minor error for almost 2 days now.

How do I use variables in document.getElementById

I have this code which I've been trying to fix for hours.
<script language="JavaScript">
<!--
function generate(){
var titels = new Array();
var i = 0;
for(i;i<9;i++){
var test = 'h1-0'+ i;
titels[i] = document.getElementById(test).textContent;
}
document.getElementById("uitkomst").value = titels[1];
}
-->
</script>
This gives me the error
TypeError: document.getElementById(...) is null
titels[i] = document.getElementById(test).textContent;
But when I change 'h1-0'+i by 'h1-0'+5 it does work and I don't get an error, so how do I fix this? Why is Javascript so annoying when using variables?

Add another variable:
var element;
and use it in the loop to hold on to the result of fetching (or trying to fetch) the element:
for (i; i < 9; i++) {
element = document.getElementById('h1-0' + i);
if (element) {
titles[i] = element.textContent;
}
else {
console.log("Element " + i + " not found.");
}
}
Then check the console to see which one is missing.

There are a couple ways you can fix this issue - you can test for a missing object and skip that case or you can catch the exception that is thrown and act accordingly in the exception handler.
Here's how you could handle missing objects in your code:
function generate(){
var titels = [];
var i, item, test;
for (i = 0; i < 9; i++) {
test = 'h1-0'+ i;
item = document.getElementById(test);
if (item) {
titels[i] = item.textContent;
}
}
document.getElementById("uitkomst").value = titels[1];
}
If, this is really all your code is doing, then you don't need the for loop because you're only using the [1] item from the array and you can do this:
function generate() {
var item = document.getElementById("h1-01");
if (item) {
document.getElementById("uitkomst").value = item.textContent;
}
}

Adding onclick event in JavaScript with parameters

I'm trying to make a dropdown to display the results of a request given what the user writes in a field.
The problem I'm encountering is that when I try to add an onclick event to each item in the dropdown, only the last one acts like expected.
The dropdown is a section and I try to include sections in it.
Here is the dropdown :
<section id="projectDrop">
</section>
Here is the code :
var j = 0;
var tmp;
for (var i=0;((i<infos.projects.length) && (i<5));i++)
{
if (infos.projects[i].name.toLowerCase().match(projectName.value.toLowerCase()))
{
projectDrop.innerHTML += '<section id="project' + j + '">' + infos.projects[i].name + '</section>';
tmp = document.getElementById('project' + j);
projectDrop.style.height = (j+1)*20 + 'px';
tmp.style.top = j*20 + 'px';
tmp.style.height = '20 px';
tmp.style.width = '100%';
tmp.style.color = 'rgb(0, 0, 145)';
tmp.style.textAlign = 'center';
tmp.style.cursor = 'pointer';
tmp.style.zIndex = 5;
tmp.onclick = function(name, key)
{
return function()
{
return insertProject(name, key);
};
} (infos.projects[i].name, infos.projects[i].key);
++j;
}
}
The result is visually as I expected, I can see the dropdown with all my projects listed and a pointer while hovering etc...
But only the last project is clickable and trigger the "insertProject" function while the other do nothing.
If someone could help me solve that !

You need to store the key somewhere. Take a look at the solution below, I have used the data-key attribute on the <section> to store the key.
Also note how I have changed the code to create the element object and assign its properties, instead of building a raw string of HTML. The problem with building HTML as a string is you have to worry about escaping quotes, whereas this way you don't.
var j = 0;
var tmp;
for (var i=0;((i<infos.projects.length) && (i<5));i++)
{
if (infos.projects[i].name.toLowerCase().match(projectName.value.toLowerCase()))
{
tmp = document.createElement('section');
tmp.id = "project" + j;
tmp.setAttribute('data-key', infos.projects[i].key);
tmp.innerHTML = infos.projects[i].name;
projectDrop.style.height = (j+1)*20 + 'px';
tmp.style.top = j*20 + 'px';
tmp.style.height = '20 px';
tmp.style.width = '100%';
tmp.style.color = 'rgb(0, 0, 145)';
tmp.style.textAlign = 'center';
tmp.style.cursor = 'pointer';
tmp.style.zIndex = 5;
tmp.onclick = function(){
insertProject(this.innerHTML, this.getAttribute('data-key'));
};
projectDrop.appendChild(tmp);
++j;
}
}

Change:
tmp.onclick = function(name, key)
{
return function()
{
return insertProject(name, key);
};
} (infos.projects[i].name, infos.projects[i].key);
to
tmp.onclick = function(j){
return function(name, key)
{
return function()
{
return insertProject(name, key);
};
} (infos.projects[j].name, infos.projects[j].key);
}(i)

Overriding javascript built in to 3rd party control (infragistics UltraWebGrid)

I am using an old version of UltraWebGrid by Infragistics and need to replace some of the built in javascript. The compiled js looks like its adding a bunch of functions to an object type as an api of sorts. formatted like:
var igtbl_ptsBand = ["functionname1",function(){...},"functionname2",function(){...},...
and so on. How would I override this?
Basically the control is adding html to the page in a way that is not compatible with newer browsers and the javascript code that does this just needs a little tweak. I found the code... I just need to change it.
The code can be found here
I added an answer to dump code examples in and whatnot. I will not select this answer
Similar SO question

The array you mentioned seems to be a function table of sorts:
var igtbl_ptsBand = ["func1", function() { }, "func2", function() { } ]
I would recommend using chaining instead of just an override. With chaining you can inject your own code, but still call the original function. Let's say you want to replace "func2" and chain. You could do something like this:
var origFunc, findex, ix;
if (igtbl_ptsBand.indexOf) {
// indexOf is supported, use it
findex = igtbl_ptsBand.indexOf("func2") + 1;
} else {
// Crippled browser such as IE, no indexOf, use loop
findex = -1;
for (ix = 0; ix < igtbl_ptsBand.length; ix += 2) {
if (igtbl_ptsBand[ix] === "func2") {
findex = ix + 1;
break;
}
}
}
if (findex >= 0) {
// Found it, chain
origFunc = igtbl_ptsBand[findex];
igtbl_ptsBand[findex] = function() {
// Your new pre-code here
// Call original func (chain)
origFunc();
// Your new post-code here
};
}
origFunc may have arguments, of course, and you may want to use the JavaScript call() function to set the "this pointer" to something specific, e.g.:
origFunc.call(customThis, arg1, arg2...);
If the arguments are in an array, you can use apply() instead of call().

I would not recommend doing this. You should always try to work with a third party library, not against it. That being said, this should work:
igtbl_ptsBand[igtbl_ptsBand.indexOf("functionYouWantToOverwrite") + 1] = function () {
// your new stuff...
};

Ok here is what I am doing. I will update this with my progress.
This fixes my problem. It turns out I had to apply the functionarray to all child objects of the parent "rows". To do this I added the code in my "Fix Rows" function. I split it up because i am running accross other browser JS error which I am fixing in this js file.
Here is the js file that I added to my .net page like so...
</form>
<script type="text/javascript" src="../../scripts/BrowserCompat.js"></script>
</body>
</html>
.
Brows_FixUltraWebGrid();
function Brows_FixUltraWebGrid() {
FixRows();
}
function FixRows() {
FixGridRows_render();
for (var i = 0; i < igtbl_ptsRows.length; i += 2)
igtbl_Rows.prototype[igtbl_ptsRows[i]] = igtbl_ptsRows[i + 1];
}
function FixGridRows_render() {
var origFunc, findex, ix;
if (igtbl_ptsRows.indexOf) {
// indexOf is supported, use it
findex = igtbl_ptsRows.indexOf("render") + 1;
} else {
// Crippled browser such as IE, no indexOf, use loop
findex = -1;
for (ix = 0; ix < igtbl_ptsRows.length; ix += 2) {
if (igtbl_ptsRows[ix] === "render") {
findex = ix + 1;
break;
}
}
}
if (findex >= 0) {
// Found it, chain
origFunc = igtbl_ptsRows[findex];
igtbl_ptsRows[findex] = function() {
// Your new pre-code here
// Call original func (chain)
//origFunc();
// Your new post-code here
var strTransform = this.applyXslToNode(this.Node);
if (strTransform) {
var anId = (this.AddNewRow ? this.AddNewRow.Id : null);
//new logic to include tbody if it is not there
var tadd1 = '';
var tadd2 = '';
if (!(/\<tbody\>/.test(strTransform))) {
tadd1 = '<tbody>';
tadd2 = '</tbody>';
}
this.Grid._innerObj.innerHTML =
"<table style=\"table-layout:fixed;\">" + tadd1 + strTransform + tadd2 + "</table>";
//old line
//this.Grid._innerObj.innerHTML = "<table style=\"table-layout:fixed;\">" + strTransform + "</table>";
var tbl = this.Element.parentNode;
igtbl_replaceChild(tbl, this.Grid._innerObj.firstChild.firstChild, this.Element);
igtbl_fixDOEXml();
var _b = this.Band;
var headerDiv = igtbl_getElementById(this.Grid.Id + "_hdiv");
var footerDiv = igtbl_getElementById(this.Grid.Id + "_fdiv");
if (this.AddNewRow) {
if (_b.Index > 0 || _b.AddNewRowView == 1 && !headerDiv || _b.AddNewRowView == 2 && !footerDiv) {
var anr = this.AddNewRow.Element;
anr.parentNode.removeChild(anr);
if (_b.AddNewRowView == 1 && tbl.tBodies[0].rows.length > 0)
tbl.tBodies[0].insertBefore(anr, tbl.tBodies[0].rows[0]);
else
tbl.tBodies[0].appendChild(anr);
}
this.AddNewRow.Element = igtbl_getElementById(anId);
this.AddNewRow.Element.Object = this.AddNewRow;
}
this.Element = tbl.tBodies[0];
this.Element.Object = this;
this._setupFilterRow();
for (var i = 0; i < this.Band.Columns.length; i++) {
var column = this.Band.Columns[i];
if (column.Selected && column.hasCells()) {
var col = this.getColumn(i);
if (col)
igtbl_selColRI(this.Grid.Id, col, this.Band.Index, i);
}
}
if (this.ParentRow) {
this.ParentRow.ChildRowsCount = this.length;
this.ParentRow.VisChildRowsCount = this.length;
}
}
console.log('overridden row render function executed');
};
}
}

building a database string

I'm trying to build a database based on some arbitrary data on a website. It's complex and changes for each site so I'll spare the details. Here's basically what I'm trying to do
function level0(arg) { textarea.innerHTML += arg + ' = {'; }
function level1(arg) { textarea.innerHTML += '\n\t' + arg + ': ['; }
function level2(arg) { textarea.innerHTML += arg + ', '; }
And so on. The thing is some level1's don't have any children and I can't get the formatting right.
My three problems are as follows.
The ending commas are going to break in IE (thank you MS)
Empty level1's shouldn't be printed if they don't have any children
Closing /curly?brackets/
HERE'S A DEMO of what I have so far. Notice the ending commas, the empty sub2 which shouldn't be printed, and no closing brackets or braces
Do I need to redesign the entire thing?
Is there also a way to have this all in one function so I don't have to worry if I add another layer?
EDIT
This needs to be done in a string format, I can't build an object and then stringify it, mostly because I need to know which element I'm in the middle of adding to.

Overall it looks that you still might want to build an object, but in case you insist on not building it - here is some sample solution:
function Printer() {
var result = '',
lastLevel = null,
close = {0:'\n}', 1:']', 2:''},
delimiter = {0: ',\n', 1:',\n', 2:','};
function closeLevel(level, noDelimiter) {
if(lastLevel === null)
return;
var l = lastLevel, d = level == lastLevel;
while(l >= level) {
result += close[l] + (l == level && !noDelimiter ? delimiter[l]:'');
l--;
}
}
this.level0 = function(arg) {
closeLevel(0);
result += arg + ' = {\n';
lastLevel = 0;
};
this.level1 = function(arg) {
closeLevel(1);
result += '\t' + arg + ': [';
lastLevel = 1;
};
this.level2 = function(arg) {
closeLevel(2);
result += arg;
lastLevel = 2;
};
this.getResult = function() {
closeLevel(lastLevel, true);
return result;
}
}
var p = new Printer();
p.level0('head');
p.level1('sub1');
p.level2('item1');p.level2('item2');p.level2('item3');
p.level1('sub2');
p.level1('sub3');
p.level2('newthing');
p.level0('head2');
document.getElementById('textarea').value = p.getResult();
You could see it in action here.

I'm not sure why you're building what looks like objects with nested arrays, using string concatenation. Something like this would be much simpler, since it wouldn't require fixing trailing commas, etc:
Edit: I've updated the code to make it keep track of the last level put in.
function Db() {
var level0, level1;
var data = new Object();
this.level0 = function(arg) {
level0 = new Object();
data[arg] = level0;
}
this.level1 = function(arg) {
level1 = new Array();
level0[arg] = level1;
}
this.level2 = function(arg) {
level1.push(arg);
}
this.toString = function() {
var s = '';
for(i in data) {
s += i + '\n';
for(j in data[i]) {
if(data[i][j].length>0) {
s += '\t' + j + ': [' + data[i][j] + ']\n' ;
}
}
}
return s;
}
}
Use like this:
var db = new Db();
db.level0('head');
db.level1('sub1');
db.level2('item1');db.level2('item2');db.level2('item3');
I've tested this in the demo you linked and it works just fine.