Question

I have created this code its make to store a table in a variable when i press save and return back to that state when i press restore but i seem to come across a runtime error on the last code (the Id of the table is sudoku) it works in firefox but not IE, Thanks

var clone
function save()
{
    var table = document.getElementById("sudoku")
    clone = table.innerHTML
}

function restore()
{
    document.getElementById("sudoku").innerHTML=clone
}

Edit:
Error Message:

Webpage error details User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; CPNTDF; .NET4.0E; .NET4.0C; BOIE9;ENUS) Timestamp: Mon, 15 Oct 2012 16:57:44 UTC Message: Unknown runtime error Line: 50 Char: 128 Code: 0 URI: file:///F:/uni%20work/home/Second%20year/CO525/assessments/Assessment2/assessmen‌​t2/javascript.js Message: Unknown runtime error Line: 50 Char: 128 Code: 0 URI: file:///F:/uni%20work/home/Second%20year/CO525/assessments/Assessment2/assessmen‌​t2/javascript.js

edit
full code:

    var current_cell = null; // the currently selected cell
    var saved = {};     // Object for saving the current game
    function initialize() {
var col, row;
// Work through all the cells in the table and set
// onclick event handlers and classNames for the empty
// ones.
for (row = 0; row <=8; row++) {
    for (col=0; col <= 8; col++) {
        var cell = document.getElementById('cell_' + col + '_' + row);
        if (!parseInt(cell.innerHTML)) {
            // cell is empty
            cell.onclick = selectCell;
            cell.className = 'tofill';
        }
    }
}
document.onkeypress = keyPress;
save();
    }
    var current_cell = null; // the currently selected cell
    var saved = {};     // Object for saving the current game
    function initialize() {
var col, row;
// Work through all the cells in the table and set
// onclick event handlers and classNames for the empty
// ones.
for (row = 0; row <=8; row++) {
    for (col=0; col <= 8; col++) {
        var cell = document.getElementById('cell_' + col + '_' + row);
        if (!parseInt(cell.innerHTML)) {
            // cell is empty
            cell.onclick = selectCell;
            cell.className = 'tofill';
        }
    }
}
document.onkeypress = keyPress;
save();
    }

    // mouse button event handler
    function selectCell() {
if (current_cell !== null) {
    current_cell.className = 'tofill';
}
current_cell = this;
current_cell.className = 'selected';
    }

    // Capture keyboard key presses. If the key pressed is a digit
    // then add it to the current cell. If it is a space then empty
    // the current cell.
    function keyPress(evt) {
if (current_cell == null)
    return;
var key;
if (evt)
    // firefox or chrome
    key = String.fromCharCode(evt.charCode);
else
    // IE
    key = String.fromCharCode(event.keyCode);
if (key == ' ')
    current_cell.innerHTML = '';
else if (key >= '1' && key <= '9')
    current_cell.innerHTML = key;
    }

    var clone
    function save()
    {
    var table = document.getElementById("sudoku");
    clone = table.innerHTML;
    }

   function restore()
    {
    document.getElementById("sudoku").innerHTML=clone;
   }

Answer 1

You can use DOM inbuilt javascript method cloneNode to clone your node..

E.G.

 var clone;
    function save()
    {
        var table = document.getElementById("sudoku");
        clone = table.cloneNode(true);
    }

    function restore()
    {
        document.getElementById("sudoku").parentNode.appendChild(clone);
    }

FOR Reference: https://developer.mozilla.org/en-US/docs/DOM/Node.cloneNode