php with javascript

hi all
i made a php page on it function with javascript to swap two images
and then i call this function on php code put it is not working

code
<SCRIPT LANGUAGE=JavaScript>
intImage = 2;
function swapImage() {
switch (intImage) {
case 1:
IMG1.src = "b_no.JPG"
intImage = 2
return(false);
case 2:
IMG1.src = "b_ok.JPG"
intImage = 1
return(false);
}
}
</SCRIPT>

php:::::
while ($threads = mysql_fetch_array($tr)) {
echo "<td> <IMG id='IMG1' name='IMG1' src='b_no.JPG'
onclick='swapImage();'></td>";


i want help plzzz

 

based on your javascript, php can do it alone

convert you js function to a php function

 

how i canot undersatand???

 

can you give me the code because i tried it and not working