There is something in this javascript or html which is is allowing the checkboxes to be ticked but for not even half a second. (I need the checks to stay there!) I also need the additems function to work
var computer = new Array();
computer[0] = "10001, Nvidia Geforce GTX 690, 1200";
computer[1] = "10002, Raedon HD 7950, 450";
computer[2] = "20001, Ivy Bridge i7 3770, 400";
computer[3] = "20002, Ivy Bridge i7 3770k, 420";
computer[4] = "20003, Sandy Bridge i7 2700k, 340";
computer[5] = "20004, Bulldozer FX-8150, 270";
computer[6] = "30001, Antec eleven-hundred, 120";
computer[7] = "30002, Coolermaster HAF-X, 170";
computer[8] = "30003, Antec three-hundred, 50";
computer[9] = "30004, Corsair 550D, 160";
computer[10] = "40001, INTEL-ASrock fatal1ty Z77 Professional Motherboard, 250";
computer[11] = "40002, INTEL-ASrock Z77 extreme9 Motherboard, 350";
computer[12] = "40003, AMD-ASrock fatal1ty 990FX Professional Motherboard, 240";
computer[13] = "40004, AMD-ASUS Sabertooth 990FX Motherboard, 260";
Check all checkboxes function
function check() {
var leftSide = document.getElementById('table_container_left');
var inputs = leftSide.getElementsByTagName('input');
for (x=0; x<=inputs.length-1; x++) {
if(inputs[x].type == 'text') {
inputs[x].value = 1;
} else {
inputs[x].checked = true;
}
}
}
Uncheck all checkboxes function
function uncheck() {
var leftSide = document.getElementById('table_container_left');
var inputs = leftSide.getElementsByTagName('input');
for (x=0; x<=inputs.length-1; x++) {
if(inputs[x].type == 'text') {
inputs[x].value = 0;
} else {
inputs[x].checked = false;
}
}
}
add checked items to cart
function addItems() {
var leftSide = document.getElementById('table_container_left');
var rightSide = document.getElementById('table_container_right');
var inputs = leftSide.getElementByTagName('input');
var totalPrice = 0;
var basketTable = "<h3>My Basket:</h3><table><thead><tr><th>Item</th><th>Quantity</th><th>price</th><th>Sub-total</th></tr></thead><tbody>";
for (x=0; x<=inputs.length-1; x++) {
if(inputs[x].type == 'checkbox' && inputs[x].checked == true) {
var quantity = ParseFloat(inputs[x+1).value);
var itemName = computer[x/2].split(",")[1];
var itemPrice = parseFloat(computer[x/2].split(",")[2])
var itemTotal = parseFloat(quantity*itemPrice);
totalPrice += itemTotal;
basketTable += "<tr><td>"+itemName+"</td><td>"+quantity+"</td><td>$"+itemPrice+"</td><td>$"+itemTotal+"</td></tr>";
}
}
basketTable +=" <tr><td> colspan='3'><b>Total:</b></td><td><b>$"+totalPrice+"</b></td></tr></tbody><table>";
rightsSide.innerHTML = basketTable;
}
update quantity to 1 when item is checked
function updateQty(id) {
var targetRow = document.getElementById(id);
var qtyBox = targetRow.getElementsByTagName('input')[1];
if (qtyBox.value == 0) {
qtyBox.value = 1;
} else {
qtyBox.value = 0;
}
}
Here's the HTML as requested
<form name="myForm" action="index.html" method="post">
<div id="table_container_left">
<button onclick="check();">Select All</button>
<button onclick="uncheck();">Unselect All</button>
<button onclick="addItems();">Add Items</button>
<table>
<thead>
<th><u>Item Code</u></th>
<th><u>Item</u></th>
<th><u>Qty</u></th>
<th><u>Price</u></th>
</thead>
<tbody>
<script type="text/javascript">
for(x=0; x<=computer.length-1; x++) {
document.write("<tr id='"+x+"'><td><label><input type='checkbox' name='item' value='"+x+"' onclick='updateQty('"+x+"');'/> "+computer[x].split(",")[0]+"</label></td><td>"+computer[x].split (",")[1]+"</td><td> <input name='qty' id='qty' type='textbox' value='0' onchange='qtychange ('"+x+"');'/></td><td>$"+computer[x].split(",")[2]+"</td></tr>");
}
</script>
</tbody>
</table>
</div>
<div id="table_container_right">
<table id="shoppingBasket">
<input name='selectAll' type='button' value='Select All' onclick="itemSelected();"/>
<input name='clearAll' type='button' value='Clear All' onclick=""/>
<input name='removeItem(s)' type='button' value='Remove Item(s)' />
<input name='sortItemCode' type='button' value='Sort by Item Code' disabled='disabled' />
<input name='sortPrice' type='button' value='Sort by Price' disabled='disabled' />
</tbody>
</table>
</div>
</div>
</form>
Your JS syntax is way off, this is what it should look like
function addItems(field) {
for (i = 0; i <= field.length-1; i++)
{
if (field[i].checked == true)
{
if (computer[i]!=null) {
selected[i] = computer[i];
}
}
}
}
Half of your if statements are missing parentheses, that's some basic wrongfulness.
I don't know what and where should any of the variables be, but here is my best shot:
function addItems(field) {
var i;
for (i = 0; i < field.length; i++) {
if (field[i].checked === true) {
if (computer[i] !== null) {
selected[i] = computer[i];
}
}
}
}
You are using i = 0 rather than var i = 0, which will introduce a global variable. This could be a problem if you're writing similar code elsewhere.
Your if-statements are not statements at all. They look like pseudo-code. You're also comparing with = rather than ==, which will cause an assignment rather than a condition, even if you fix up your syntax.
You are not properly indenting your code, which will make you much more prone to introduce new errors.
These are the general issues I notice immediately. Of course, heaps of things could be wrong with this code. fields might not be an array, computer and selected might not match the size of fields, etc.
If you have any specific problem, please describe that, and we may be able to address it.
来源：https://stackoverflow.com/questions/11517129/what-is-wrong-with-this-javascript-shopping-cart